// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2018, The Linux Foundation. All rights reserved. * datasheet: https://www.ti.com/lit/ds/symlink/sn65dsi86.pdf */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define SN_DEVICE_REV_REG 0x08 #define SN_DPPLL_SRC_REG 0x0A #define DPPLL_CLK_SRC_DSICLK BIT(0) #define REFCLK_FREQ_MASK GENMASK(3, 1) #define REFCLK_FREQ(x) ((x) << 1) #define DPPLL_SRC_DP_PLL_LOCK BIT(7) #define SN_PLL_ENABLE_REG 0x0D #define SN_DSI_LANES_REG 0x10 #define CHA_DSI_LANES_MASK GENMASK(4, 3) #define CHA_DSI_LANES(x) ((x) << 3) #define SN_DSIA_CLK_FREQ_REG 0x12 #define SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG 0x20 #define SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG 0x24 #define SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG 0x2C #define SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG 0x2D #define CHA_HSYNC_POLARITY BIT(7) #define SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG 0x30 #define SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG 0x31 #define CHA_VSYNC_POLARITY BIT(7) #define SN_CHA_HORIZONTAL_BACK_PORCH_REG 0x34 #define SN_CHA_VERTICAL_BACK_PORCH_REG 0x36 #define SN_CHA_HORIZONTAL_FRONT_PORCH_REG 0x38 #define SN_CHA_VERTICAL_FRONT_PORCH_REG 0x3A #define SN_LN_ASSIGN_REG 0x59 #define LN_ASSIGN_WIDTH 2 #define SN_ENH_FRAME_REG 0x5A #define VSTREAM_ENABLE BIT(3) #define LN_POLRS_OFFSET 4 #define LN_POLRS_MASK 0xf0 #define SN_DATA_FORMAT_REG 0x5B #define BPP_18_RGB BIT(0) #define SN_HPD_DISABLE_REG 0x5C #define HPD_DISABLE BIT(0) #define HPD_DEBOUNCED_STATE BIT(4) #define SN_GPIO_IO_REG 0x5E #define SN_GPIO_INPUT_SHIFT 4 #define SN_GPIO_OUTPUT_SHIFT 0 #define SN_GPIO_CTRL_REG 0x5F #define SN_GPIO_MUX_INPUT 0 #define SN_GPIO_MUX_OUTPUT 1 #define SN_GPIO_MUX_SPECIAL 2 #define SN_GPIO_MUX_MASK 0x3 #define SN_AUX_WDATA_REG(x) (0x64 + (x)) #define SN_AUX_ADDR_19_16_REG 0x74 #define SN_AUX_ADDR_15_8_REG 0x75 #define SN_AUX_ADDR_7_0_REG 0x76 #define SN_AUX_ADDR_MASK GENMASK(19, 0) #define SN_AUX_LENGTH_REG 0x77 #define SN_AUX_CMD_REG 0x78 #define AUX_CMD_SEND BIT(0) #define AUX_CMD_REQ(x) ((x) << 4) #define SN_AUX_RDATA_REG(x) (0x79 + (x)) #define SN_SSC_CONFIG_REG 0x93 #define DP_NUM_LANES_MASK GENMASK(5, 4) #define DP_NUM_LANES(x) ((x) << 4) #define SN_DATARATE_CONFIG_REG 0x94 #define DP_DATARATE_MASK GENMASK(7, 5) #define DP_DATARATE(x) ((x) << 5) #define SN_TRAINING_SETTING_REG 0x95 #define SCRAMBLE_DISABLE BIT(4) #define SN_ML_TX_MODE_REG 0x96 #define ML_TX_MAIN_LINK_OFF 0 #define ML_TX_NORMAL_MODE BIT(0) #define SN_PWM_PRE_DIV_REG 0xA0 #define SN_BACKLIGHT_SCALE_REG 0xA1 #define BACKLIGHT_SCALE_MAX 0xFFFF #define SN_BACKLIGHT_REG 0xA3 #define SN_PWM_EN_INV_REG 0xA5 #define SN_PWM_INV_MASK BIT(0) #define SN_PWM_EN_MASK BIT(1) #define SN_AUX_CMD_STATUS_REG 0xF4 #define AUX_IRQ_STATUS_AUX_RPLY_TOUT BIT(3) #define AUX_IRQ_STATUS_AUX_SHORT BIT(5) #define AUX_IRQ_STATUS_NAT_I2C_FAIL BIT(6) #define MIN_DSI_CLK_FREQ_MHZ 40 /* fudge factor required to account for 8b/10b encoding */ #define DP_CLK_FUDGE_NUM 10 #define DP_CLK_FUDGE_DEN 8 /* Matches DP_AUX_MAX_PAYLOAD_BYTES (for now) */ #define SN_AUX_MAX_PAYLOAD_BYTES 16 #define SN_REGULATOR_SUPPLY_NUM 4 #define SN_MAX_DP_LANES 4 #define SN_NUM_GPIOS 4 #define SN_GPIO_PHYSICAL_OFFSET 1 #define SN_LINK_TRAINING_TRIES 10 #define SN_PWM_GPIO_IDX 3 /* 4th GPIO */ /** * struct ti_sn65dsi86 - Platform data for ti-sn65dsi86 driver. * @bridge_aux: AUX-bus sub device for MIPI-to-eDP bridge functionality. * @gpio_aux: AUX-bus sub device for GPIO controller functionality. * @aux_aux: AUX-bus sub device for eDP AUX channel functionality. * @pwm_aux: AUX-bus sub device for PWM controller functionality. * * @dev: Pointer to the top level (i2c) device. * @regmap: Regmap for accessing i2c. * @aux: Our aux channel. * @bridge: Our bridge. * @connector: Our connector. * @host_node: Remote DSI node. * @dsi: Our MIPI DSI source. * @refclk: Our reference clock. * @next_bridge: The bridge on the eDP side. * @enable_gpio: The GPIO we toggle to enable the bridge. * @supplies: Data for bulk enabling/disabling our regulators. * @dp_lanes: Count of dp_lanes we're using. * @ln_assign: Value to program to the LN_ASSIGN register. * @ln_polrs: Value for the 4-bit LN_POLRS field of SN_ENH_FRAME_REG. * @comms_enabled: If true then communication over the aux channel is enabled. * @comms_mutex: Protects modification of comms_enabled. * * @gchip: If we expose our GPIOs, this is used. * @gchip_output: A cache of whether we've set GPIOs to output. This * serves double-duty of keeping track of the direction and * also keeping track of whether we've incremented the * pm_runtime reference count for this pin, which we do * whenever a pin is configured as an output. This is a * bitmap so we can do atomic ops on it without an extra * lock so concurrent users of our 4 GPIOs don't stomp on * each other's read-modify-write. * * @pchip: pwm_chip if the PWM is exposed. * @pwm_enabled: Used to track if the PWM signal is currently enabled. * @pwm_pin_busy: Track if GPIO4 is currently requested for GPIO or PWM. * @pwm_refclk_freq: Cache for the reference clock input to the PWM. */ struct ti_sn65dsi86 { struct auxiliary_device *bridge_aux; struct auxiliary_device *gpio_aux; struct auxiliary_device *aux_aux; struct auxiliary_device *pwm_aux; struct device *dev; struct regmap *regmap; struct drm_dp_aux aux; struct drm_bridge bridge; struct drm_connector *connector; struct device_node *host_node; struct mipi_dsi_device *dsi; struct clk *refclk; struct drm_bridge *next_bridge; struct gpio_desc *enable_gpio; struct regulator_bulk_data supplies[SN_REGULATOR_SUPPLY_NUM]; int dp_lanes; u8 ln_assign; u8 ln_polrs; bool comms_enabled; struct mutex comms_mutex; #if defined(CONFIG_OF_GPIO) struct gpio_chip gchip; DECLARE_BITMAP(gchip_output, SN_NUM_GPIOS); #endif #if defined(CONFIG_PWM) struct pwm_chip pchip; bool pwm_enabled; atomic_t pwm_pin_busy; #endif unsigned int pwm_refclk_freq; }; static const struct regmap_range ti_sn65dsi86_volatile_ranges[] = { { .range_min = 0, .range_max = 0xFF }, }; static const struct regmap_access_table ti_sn_bridge_volatile_table = { .yes_ranges = ti_sn65dsi86_volatile_ranges, .n_yes_ranges = ARRAY_SIZE(ti_sn65dsi86_volatile_ranges), }; static const struct regmap_config ti_sn65dsi86_regmap_config = { .reg_bits = 8, .val_bits = 8, .volatile_table = &ti_sn_bridge_volatile_table, .cache_type = REGCACHE_NONE, .max_register = 0xFF, }; static int __maybe_unused ti_sn65dsi86_read_u16(struct ti_sn65dsi86 *pdata, unsigned int reg, u16 *val) { u8 buf[2]; int ret; ret = regmap_bulk_read(pdata->regmap, reg, buf, ARRAY_SIZE(buf)); if (ret) return ret; *val = buf[0] | (buf[1] << 8); return 0; } static void ti_sn65dsi86_write_u16(struct ti_sn65dsi86 *pdata, unsigned int reg, u16 val) { u8 buf[2] = { val & 0xff, val >> 8 }; regmap_bulk_write(pdata->regmap, reg, buf, ARRAY_SIZE(buf)); } static u32 ti_sn_bridge_get_dsi_freq(struct ti_sn65dsi86 *pdata) { u32 bit_rate_khz, clk_freq_khz; struct drm_display_mode *mode = &pdata->bridge.encoder->crtc->state->adjusted_mode; bit_rate_khz = mode->clock * mipi_dsi_pixel_format_to_bpp(pdata->dsi->format); clk_freq_khz = bit_rate_khz / (pdata->dsi->lanes * 2); return clk_freq_khz; } /* clk frequencies supported by bridge in Hz in case derived from REFCLK pin */ static const u32 ti_sn_bridge_refclk_lut[] = { 12000000, 19200000, 26000000, 27000000, 38400000, }; /* clk frequencies supported by bridge in Hz in case derived from DACP/N pin */ static const u32 ti_sn_bridge_dsiclk_lut[] = { 468000000, 384000000, 416000000, 486000000, 460800000, }; static void ti_sn_bridge_set_refclk_freq(struct ti_sn65dsi86 *pdata) { int i; u32 refclk_rate; const u32 *refclk_lut; size_t refclk_lut_size; if (pdata->refclk) { refclk_rate = clk_get_rate(pdata->refclk); refclk_lut = ti_sn_bridge_refclk_lut; refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_refclk_lut); clk_prepare_enable(pdata->refclk); } else { refclk_rate = ti_sn_bridge_get_dsi_freq(pdata) * 1000; refclk_lut = ti_sn_bridge_dsiclk_lut; refclk_lut_size = ARRAY_SIZE(ti_sn_bridge_dsiclk_lut); } /* for i equals to refclk_lut_size means default frequency */ for (i = 0; i < refclk_lut_size; i++) if (refclk_lut[i] == refclk_rate) break; /* avoid buffer overflow and "1" is the default rate in the datasheet. */ if (i >= refclk_lut_size) i = 1; regmap_update_bits(pdata->regmap, SN_DPPLL_SRC_REG, REFCLK_FREQ_MASK, REFCLK_FREQ(i)); /* * The PWM refclk is based on the value written to SN_DPPLL_SRC_REG, * regardless of its actual sourcing. */ pdata->pwm_refclk_freq = ti_sn_bridge_refclk_lut[i]; } static void ti_sn65dsi86_enable_comms(struct ti_sn65dsi86 *pdata) { mutex_lock(&pdata->comms_mutex); /* configure bridge ref_clk */ ti_sn_bridge_set_refclk_freq(pdata); /* * HPD on this bridge chip is a bit useless. This is an eDP bridge * so the HPD is an internal signal that's only there to signal that * the panel is done powering up. ...but the bridge chip debounces * this signal by between 100 ms and 400 ms (depending on process, * voltage, and temperate--I measured it at about 200 ms). One * particular panel asserted HPD 84 ms after it was powered on meaning * that we saw HPD 284 ms after power on. ...but the same panel said * that instead of looking at HPD you could just hardcode a delay of * 200 ms. We'll assume that the panel driver will have the hardcoded * delay in its prepare and always disable HPD. * * If HPD somehow makes sense on some future panel we'll have to * change this to be conditional on someone specifying that HPD should * be used. */ regmap_update_bits(pdata->regmap, SN_HPD_DISABLE_REG, HPD_DISABLE, HPD_DISABLE); pdata->comms_enabled = true; mutex_unlock(&pdata->comms_mutex); } static void ti_sn65dsi86_disable_comms(struct ti_sn65dsi86 *pdata) { mutex_lock(&pdata->comms_mutex); pdata->comms_enabled = false; clk_disable_unprepare(pdata->refclk); mutex_unlock(&pdata->comms_mutex); } static int __maybe_unused ti_sn65dsi86_resume(struct device *dev) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(dev); int ret; ret = regulator_bulk_enable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies); if (ret) { DRM_ERROR("failed to enable supplies %d\n", ret); return ret; } /* td2: min 100 us after regulators before enabling the GPIO */ usleep_range(100, 110); gpiod_set_value(pdata->enable_gpio, 1); /* * If we have a reference clock we can enable communication w/ the * panel (including the aux channel) w/out any need for an input clock * so we can do it in resume which lets us read the EDID before * pre_enable(). Without a reference clock we need the MIPI reference * clock so reading early doesn't work. */ if (pdata->refclk) ti_sn65dsi86_enable_comms(pdata); return ret; } static int __maybe_unused ti_sn65dsi86_suspend(struct device *dev) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(dev); int ret; if (pdata->refclk) ti_sn65dsi86_disable_comms(pdata); gpiod_set_value(pdata->enable_gpio, 0); ret = regulator_bulk_disable(SN_REGULATOR_SUPPLY_NUM, pdata->supplies); if (ret) DRM_ERROR("failed to disable supplies %d\n", ret); return ret; } static const struct dev_pm_ops ti_sn65dsi86_pm_ops = { SET_RUNTIME_PM_OPS(ti_sn65dsi86_suspend, ti_sn65dsi86_resume, NULL) SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) }; static int status_show(struct seq_file *s, void *data) { struct ti_sn65dsi86 *pdata = s->private; unsigned int reg, val; seq_puts(s, "STATUS REGISTERS:\n"); pm_runtime_get_sync(pdata->dev); /* IRQ Status Registers, see Table 31 in datasheet */ for (reg = 0xf0; reg <= 0xf8; reg++) { regmap_read(pdata->regmap, reg, &val); seq_printf(s, "[0x%02x] = 0x%08x\n", reg, val); } pm_runtime_put_autosuspend(pdata->dev); return 0; } DEFINE_SHOW_ATTRIBUTE(status); static void ti_sn65dsi86_debugfs_remove(void *data) { debugfs_remove_recursive(data); } static void ti_sn65dsi86_debugfs_init(struct ti_sn65dsi86 *pdata) { struct device *dev = pdata->dev; struct dentry *debugfs; int ret; debugfs = debugfs_create_dir(dev_name(dev), NULL); /* * We might get an error back if debugfs wasn't enabled in the kernel * so let's just silently return upon failure. */ if (IS_ERR_OR_NULL(debugfs)) return; ret = devm_add_action_or_reset(dev, ti_sn65dsi86_debugfs_remove, debugfs); if (ret) return; debugfs_create_file("status", 0600, debugfs, pdata, &status_fops); } /* ----------------------------------------------------------------------------- * Auxiliary Devices (*not* AUX) */ static void ti_sn65dsi86_uninit_aux(void *data) { auxiliary_device_uninit(data); } static void ti_sn65dsi86_delete_aux(void *data) { auxiliary_device_delete(data); } static void ti_sn65dsi86_aux_device_release(struct device *dev) { struct auxiliary_device *aux = container_of(dev, struct auxiliary_device, dev); kfree(aux); } static int ti_sn65dsi86_add_aux_device(struct ti_sn65dsi86 *pdata, struct auxiliary_device **aux_out, const char *name) { struct device *dev = pdata->dev; struct auxiliary_device *aux; int ret; aux = kzalloc(sizeof(*aux), GFP_KERNEL); if (!aux) return -ENOMEM; aux->name = name; aux->dev.parent = dev; aux->dev.release = ti_sn65dsi86_aux_device_release; device_set_of_node_from_dev(&aux->dev, dev); ret = auxiliary_device_init(aux); if (ret) { kfree(aux); return ret; } ret = devm_add_action_or_reset(dev, ti_sn65dsi86_uninit_aux, aux); if (ret) return ret; ret = auxiliary_device_add(aux); if (ret) return ret; ret = devm_add_action_or_reset(dev, ti_sn65dsi86_delete_aux, aux); if (!ret) *aux_out = aux; return ret; } /* ----------------------------------------------------------------------------- * AUX Adapter */ static struct ti_sn65dsi86 *aux_to_ti_sn65dsi86(struct drm_dp_aux *aux) { return container_of(aux, struct ti_sn65dsi86, aux); } static ssize_t ti_sn_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct ti_sn65dsi86 *pdata = aux_to_ti_sn65dsi86(aux); u32 request = msg->request & ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE); u32 request_val = AUX_CMD_REQ(msg->request); u8 *buf = msg->buffer; unsigned int len = msg->size; unsigned int val; int ret; u8 addr_len[SN_AUX_LENGTH_REG + 1 - SN_AUX_ADDR_19_16_REG]; if (len > SN_AUX_MAX_PAYLOAD_BYTES) return -EINVAL; pm_runtime_get_sync(pdata->dev); mutex_lock(&pdata->comms_mutex); /* * If someone tries to do a DDC over AUX transaction before pre_enable() * on a device without a dedicated reference clock then we just can't * do it. Fail right away. This prevents non-refclk users from reading * the EDID before enabling the panel but such is life. */ if (!pdata->comms_enabled) { ret = -EIO; goto exit; } switch (request) { case DP_AUX_NATIVE_WRITE: case DP_AUX_I2C_WRITE: case DP_AUX_NATIVE_READ: case DP_AUX_I2C_READ: regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val); /* Assume it's good */ msg->reply = 0; break; default: ret = -EINVAL; goto exit; } BUILD_BUG_ON(sizeof(addr_len) != sizeof(__be32)); put_unaligned_be32((msg->address & SN_AUX_ADDR_MASK) << 8 | len, addr_len); regmap_bulk_write(pdata->regmap, SN_AUX_ADDR_19_16_REG, addr_len, ARRAY_SIZE(addr_len)); if (request == DP_AUX_NATIVE_WRITE || request == DP_AUX_I2C_WRITE) regmap_bulk_write(pdata->regmap, SN_AUX_WDATA_REG(0), buf, len); /* Clear old status bits before start so we don't get confused */ regmap_write(pdata->regmap, SN_AUX_CMD_STATUS_REG, AUX_IRQ_STATUS_NAT_I2C_FAIL | AUX_IRQ_STATUS_AUX_RPLY_TOUT | AUX_IRQ_STATUS_AUX_SHORT); regmap_write(pdata->regmap, SN_AUX_CMD_REG, request_val | AUX_CMD_SEND); /* Zero delay loop because i2c transactions are slow already */ ret = regmap_read_poll_timeout(pdata->regmap, SN_AUX_CMD_REG, val, !(val & AUX_CMD_SEND), 0, 50 * 1000); if (ret) goto exit; ret = regmap_read(pdata->regmap, SN_AUX_CMD_STATUS_REG, &val); if (ret) goto exit; if (val & AUX_IRQ_STATUS_AUX_RPLY_TOUT) { /* * The hardware tried the message seven times per the DP spec * but it hit a timeout. We ignore defers here because they're * handled in hardware. */ ret = -ETIMEDOUT; goto exit; } if (val & AUX_IRQ_STATUS_AUX_SHORT) { ret = regmap_read(pdata->regmap, SN_AUX_LENGTH_REG, &len); if (ret) goto exit; } else if (val & AUX_IRQ_STATUS_NAT_I2C_FAIL) { switch (request) { case DP_AUX_I2C_WRITE: case DP_AUX_I2C_READ: msg->reply |= DP_AUX_I2C_REPLY_NACK; break; case DP_AUX_NATIVE_READ: case DP_AUX_NATIVE_WRITE: msg->reply |= DP_AUX_NATIVE_REPLY_NACK; break; } len = 0; goto exit; } if (request != DP_AUX_NATIVE_WRITE && request != DP_AUX_I2C_WRITE && len != 0) ret = regmap_bulk_read(pdata->regmap, SN_AUX_RDATA_REG(0), buf, len); exit: mutex_unlock(&pdata->comms_mutex); pm_runtime_mark_last_busy(pdata->dev); pm_runtime_put_autosuspend(pdata->dev); if (ret) return ret; return len; } static int ti_sn_aux_probe(struct auxiliary_device *adev, const struct auxiliary_device_id *id) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); int ret; pdata->aux.name = "ti-sn65dsi86-aux"; pdata->aux.dev = &adev->dev; pdata->aux.transfer = ti_sn_aux_transfer; drm_dp_aux_init(&pdata->aux); ret = devm_of_dp_aux_populate_ep_devices(&pdata->aux); if (ret) return ret; /* * The eDP to MIPI bridge parts don't work until the AUX channel is * setup so we don't add it in the main driver probe, we add it now. */ return ti_sn65dsi86_add_aux_device(pdata, &pdata->bridge_aux, "bridge"); } static const struct auxiliary_device_id ti_sn_aux_id_table[] = { { .name = "ti_sn65dsi86.aux", }, {}, }; static struct auxiliary_driver ti_sn_aux_driver = { .name = "aux", .probe = ti_sn_aux_probe, .id_table = ti_sn_aux_id_table, }; /*------------------------------------------------------------------------------ * DRM Bridge */ static struct ti_sn65dsi86 *bridge_to_ti_sn65dsi86(struct drm_bridge *bridge) { return container_of(bridge, struct ti_sn65dsi86, bridge); } static int ti_sn_attach_host(struct ti_sn65dsi86 *pdata) { int val; struct mipi_dsi_host *host; struct mipi_dsi_device *dsi; struct device *dev = pdata->dev; const struct mipi_dsi_device_info info = { .type = "ti_sn_bridge", .channel = 0, .node = NULL, }; host = of_find_mipi_dsi_host_by_node(pdata->host_node); if (!host) return -EPROBE_DEFER; dsi = devm_mipi_dsi_device_register_full(dev, host, &info); if (IS_ERR(dsi)) return PTR_ERR(dsi); /* TODO: setting to 4 MIPI lanes always for now */ dsi->lanes = 4; dsi->format = MIPI_DSI_FMT_RGB888; dsi->mode_flags = MIPI_DSI_MODE_VIDEO; /* check if continuous dsi clock is required or not */ pm_runtime_get_sync(dev); regmap_read(pdata->regmap, SN_DPPLL_SRC_REG, &val); pm_runtime_put_autosuspend(dev); if (!(val & DPPLL_CLK_SRC_DSICLK)) dsi->mode_flags |= MIPI_DSI_CLOCK_NON_CONTINUOUS; pdata->dsi = dsi; return devm_mipi_dsi_attach(dev, dsi); } static int ti_sn_bridge_attach(struct drm_bridge *bridge, enum drm_bridge_attach_flags flags) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); int ret; pdata->aux.drm_dev = bridge->dev; ret = drm_dp_aux_register(&pdata->aux); if (ret < 0) { drm_err(bridge->dev, "Failed to register DP AUX channel: %d\n", ret); return ret; } /* * Attach the next bridge. * We never want the next bridge to *also* create a connector. */ ret = drm_bridge_attach(bridge->encoder, pdata->next_bridge, &pdata->bridge, flags | DRM_BRIDGE_ATTACH_NO_CONNECTOR); if (ret < 0) goto err_initted_aux; if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) return 0; pdata->connector = drm_bridge_connector_init(pdata->bridge.dev, pdata->bridge.encoder); if (IS_ERR(pdata->connector)) { ret = PTR_ERR(pdata->connector); goto err_initted_aux; } drm_connector_attach_encoder(pdata->connector, pdata->bridge.encoder); return 0; err_initted_aux: drm_dp_aux_unregister(&pdata->aux); return ret; } static void ti_sn_bridge_detach(struct drm_bridge *bridge) { drm_dp_aux_unregister(&bridge_to_ti_sn65dsi86(bridge)->aux); } static enum drm_mode_status ti_sn_bridge_mode_valid(struct drm_bridge *bridge, const struct drm_display_info *info, const struct drm_display_mode *mode) { /* maximum supported resolution is 4K at 60 fps */ if (mode->clock > 594000) return MODE_CLOCK_HIGH; /* * The front and back porch registers are 8 bits, and pulse width * registers are 15 bits, so reject any modes with larger periods. */ if ((mode->hsync_start - mode->hdisplay) > 0xff) return MODE_HBLANK_WIDE; if ((mode->vsync_start - mode->vdisplay) > 0xff) return MODE_VBLANK_WIDE; if ((mode->hsync_end - mode->hsync_start) > 0x7fff) return MODE_HSYNC_WIDE; if ((mode->vsync_end - mode->vsync_start) > 0x7fff) return MODE_VSYNC_WIDE; if ((mode->htotal - mode->hsync_end) > 0xff) return MODE_HBLANK_WIDE; if ((mode->vtotal - mode->vsync_end) > 0xff) return MODE_VBLANK_WIDE; return MODE_OK; } static void ti_sn_bridge_atomic_disable(struct drm_bridge *bridge, struct drm_bridge_state *old_bridge_state) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); /* disable video stream */ regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE, 0); } static void ti_sn_bridge_set_dsi_rate(struct ti_sn65dsi86 *pdata) { unsigned int bit_rate_mhz, clk_freq_mhz; unsigned int val; struct drm_display_mode *mode = &pdata->bridge.encoder->crtc->state->adjusted_mode; /* set DSIA clk frequency */ bit_rate_mhz = (mode->clock / 1000) * mipi_dsi_pixel_format_to_bpp(pdata->dsi->format); clk_freq_mhz = bit_rate_mhz / (pdata->dsi->lanes * 2); /* for each increment in val, frequency increases by 5MHz */ val = (MIN_DSI_CLK_FREQ_MHZ / 5) + (((clk_freq_mhz - MIN_DSI_CLK_FREQ_MHZ) / 5) & 0xFF); regmap_write(pdata->regmap, SN_DSIA_CLK_FREQ_REG, val); } static unsigned int ti_sn_bridge_get_bpp(struct drm_connector *connector) { if (connector->display_info.bpc <= 6) return 18; else return 24; } /* * LUT index corresponds to register value and * LUT values corresponds to dp data rate supported * by the bridge in Mbps unit. */ static const unsigned int ti_sn_bridge_dp_rate_lut[] = { 0, 1620, 2160, 2430, 2700, 3240, 4320, 5400 }; static int ti_sn_bridge_calc_min_dp_rate_idx(struct ti_sn65dsi86 *pdata, unsigned int bpp) { unsigned int bit_rate_khz, dp_rate_mhz; unsigned int i; struct drm_display_mode *mode = &pdata->bridge.encoder->crtc->state->adjusted_mode; /* Calculate minimum bit rate based on our pixel clock. */ bit_rate_khz = mode->clock * bpp; /* Calculate minimum DP data rate, taking 80% as per DP spec */ dp_rate_mhz = DIV_ROUND_UP(bit_rate_khz * DP_CLK_FUDGE_NUM, 1000 * pdata->dp_lanes * DP_CLK_FUDGE_DEN); for (i = 1; i < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut) - 1; i++) if (ti_sn_bridge_dp_rate_lut[i] >= dp_rate_mhz) break; return i; } static unsigned int ti_sn_bridge_read_valid_rates(struct ti_sn65dsi86 *pdata) { unsigned int valid_rates = 0; unsigned int rate_per_200khz; unsigned int rate_mhz; u8 dpcd_val; int ret; int i, j; ret = drm_dp_dpcd_readb(&pdata->aux, DP_EDP_DPCD_REV, &dpcd_val); if (ret != 1) { DRM_DEV_ERROR(pdata->dev, "Can't read eDP rev (%d), assuming 1.1\n", ret); dpcd_val = DP_EDP_11; } if (dpcd_val >= DP_EDP_14) { /* eDP 1.4 devices must provide a custom table */ __le16 sink_rates[DP_MAX_SUPPORTED_RATES]; ret = drm_dp_dpcd_read(&pdata->aux, DP_SUPPORTED_LINK_RATES, sink_rates, sizeof(sink_rates)); if (ret != sizeof(sink_rates)) { DRM_DEV_ERROR(pdata->dev, "Can't read supported rate table (%d)\n", ret); /* By zeroing we'll fall back to DP_MAX_LINK_RATE. */ memset(sink_rates, 0, sizeof(sink_rates)); } for (i = 0; i < ARRAY_SIZE(sink_rates); i++) { rate_per_200khz = le16_to_cpu(sink_rates[i]); if (!rate_per_200khz) break; rate_mhz = rate_per_200khz * 200 / 1000; for (j = 0; j < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut); j++) { if (ti_sn_bridge_dp_rate_lut[j] == rate_mhz) valid_rates |= BIT(j); } } for (i = 0; i < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut); i++) { if (valid_rates & BIT(i)) return valid_rates; } DRM_DEV_ERROR(pdata->dev, "No matching eDP rates in table; falling back\n"); } /* On older versions best we can do is use DP_MAX_LINK_RATE */ ret = drm_dp_dpcd_readb(&pdata->aux, DP_MAX_LINK_RATE, &dpcd_val); if (ret != 1) { DRM_DEV_ERROR(pdata->dev, "Can't read max rate (%d); assuming 5.4 GHz\n", ret); dpcd_val = DP_LINK_BW_5_4; } switch (dpcd_val) { default: DRM_DEV_ERROR(pdata->dev, "Unexpected max rate (%#x); assuming 5.4 GHz\n", (int)dpcd_val); fallthrough; case DP_LINK_BW_5_4: valid_rates |= BIT(7); fallthrough; case DP_LINK_BW_2_7: valid_rates |= BIT(4); fallthrough; case DP_LINK_BW_1_62: valid_rates |= BIT(1); break; } return valid_rates; } static void ti_sn_bridge_set_video_timings(struct ti_sn65dsi86 *pdata) { struct drm_display_mode *mode = &pdata->bridge.encoder->crtc->state->adjusted_mode; u8 hsync_polarity = 0, vsync_polarity = 0; if (mode->flags & DRM_MODE_FLAG_NHSYNC) hsync_polarity = CHA_HSYNC_POLARITY; if (mode->flags & DRM_MODE_FLAG_NVSYNC) vsync_polarity = CHA_VSYNC_POLARITY; ti_sn65dsi86_write_u16(pdata, SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG, mode->hdisplay); ti_sn65dsi86_write_u16(pdata, SN_CHA_VERTICAL_DISPLAY_SIZE_LOW_REG, mode->vdisplay); regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_LOW_REG, (mode->hsync_end - mode->hsync_start) & 0xFF); regmap_write(pdata->regmap, SN_CHA_HSYNC_PULSE_WIDTH_HIGH_REG, (((mode->hsync_end - mode->hsync_start) >> 8) & 0x7F) | hsync_polarity); regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_LOW_REG, (mode->vsync_end - mode->vsync_start) & 0xFF); regmap_write(pdata->regmap, SN_CHA_VSYNC_PULSE_WIDTH_HIGH_REG, (((mode->vsync_end - mode->vsync_start) >> 8) & 0x7F) | vsync_polarity); regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_BACK_PORCH_REG, (mode->htotal - mode->hsync_end) & 0xFF); regmap_write(pdata->regmap, SN_CHA_VERTICAL_BACK_PORCH_REG, (mode->vtotal - mode->vsync_end) & 0xFF); regmap_write(pdata->regmap, SN_CHA_HORIZONTAL_FRONT_PORCH_REG, (mode->hsync_start - mode->hdisplay) & 0xFF); regmap_write(pdata->regmap, SN_CHA_VERTICAL_FRONT_PORCH_REG, (mode->vsync_start - mode->vdisplay) & 0xFF); usleep_range(10000, 10500); /* 10ms delay recommended by spec */ } static unsigned int ti_sn_get_max_lanes(struct ti_sn65dsi86 *pdata) { u8 data; int ret; ret = drm_dp_dpcd_readb(&pdata->aux, DP_MAX_LANE_COUNT, &data); if (ret != 1) { DRM_DEV_ERROR(pdata->dev, "Can't read lane count (%d); assuming 4\n", ret); return 4; } return data & DP_LANE_COUNT_MASK; } static int ti_sn_link_training(struct ti_sn65dsi86 *pdata, int dp_rate_idx, const char **last_err_str) { unsigned int val; int ret; int i; /* set dp clk frequency value */ regmap_update_bits(pdata->regmap, SN_DATARATE_CONFIG_REG, DP_DATARATE_MASK, DP_DATARATE(dp_rate_idx)); /* enable DP PLL */ regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 1); ret = regmap_read_poll_timeout(pdata->regmap, SN_DPPLL_SRC_REG, val, val & DPPLL_SRC_DP_PLL_LOCK, 1000, 50 * 1000); if (ret) { *last_err_str = "DP_PLL_LOCK polling failed"; goto exit; } /* * We'll try to link train several times. As part of link training * the bridge chip will write DP_SET_POWER_D0 to DP_SET_POWER. If * the panel isn't ready quite it might respond NAK here which means * we need to try again. */ for (i = 0; i < SN_LINK_TRAINING_TRIES; i++) { /* Semi auto link training mode */ regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0x0A); ret = regmap_read_poll_timeout(pdata->regmap, SN_ML_TX_MODE_REG, val, val == ML_TX_MAIN_LINK_OFF || val == ML_TX_NORMAL_MODE, 1000, 500 * 1000); if (ret) { *last_err_str = "Training complete polling failed"; } else if (val == ML_TX_MAIN_LINK_OFF) { *last_err_str = "Link training failed, link is off"; ret = -EIO; continue; } break; } /* If we saw quite a few retries, add a note about it */ if (!ret && i > SN_LINK_TRAINING_TRIES / 2) DRM_DEV_INFO(pdata->dev, "Link training needed %d retries\n", i); exit: /* Disable the PLL if we failed */ if (ret) regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 0); return ret; } static void ti_sn_bridge_atomic_enable(struct drm_bridge *bridge, struct drm_bridge_state *old_bridge_state) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); struct drm_connector *connector; const char *last_err_str = "No supported DP rate"; unsigned int valid_rates; int dp_rate_idx; unsigned int val; int ret = -EINVAL; int max_dp_lanes; unsigned int bpp; connector = drm_atomic_get_new_connector_for_encoder(old_bridge_state->base.state, bridge->encoder); if (!connector) { dev_err_ratelimited(pdata->dev, "Could not get the connector\n"); return; } max_dp_lanes = ti_sn_get_max_lanes(pdata); pdata->dp_lanes = min(pdata->dp_lanes, max_dp_lanes); /* DSI_A lane config */ val = CHA_DSI_LANES(SN_MAX_DP_LANES - pdata->dsi->lanes); regmap_update_bits(pdata->regmap, SN_DSI_LANES_REG, CHA_DSI_LANES_MASK, val); regmap_write(pdata->regmap, SN_LN_ASSIGN_REG, pdata->ln_assign); regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, LN_POLRS_MASK, pdata->ln_polrs << LN_POLRS_OFFSET); /* set dsi clk frequency value */ ti_sn_bridge_set_dsi_rate(pdata); /* * The SN65DSI86 only supports ASSR Display Authentication method and * this method is enabled for eDP panels. An eDP panel must support this * authentication method. We need to enable this method in the eDP panel * at DisplayPort address 0x0010A prior to link training. * * As only ASSR is supported by SN65DSI86, for full DisplayPort displays * we need to disable the scrambler. */ if (pdata->bridge.type == DRM_MODE_CONNECTOR_eDP) { drm_dp_dpcd_writeb(&pdata->aux, DP_EDP_CONFIGURATION_SET, DP_ALTERNATE_SCRAMBLER_RESET_ENABLE); regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG, SCRAMBLE_DISABLE, 0); } else { regmap_update_bits(pdata->regmap, SN_TRAINING_SETTING_REG, SCRAMBLE_DISABLE, SCRAMBLE_DISABLE); } bpp = ti_sn_bridge_get_bpp(connector); /* Set the DP output format (18 bpp or 24 bpp) */ val = bpp == 18 ? BPP_18_RGB : 0; regmap_update_bits(pdata->regmap, SN_DATA_FORMAT_REG, BPP_18_RGB, val); /* DP lane config */ val = DP_NUM_LANES(min(pdata->dp_lanes, 3)); regmap_update_bits(pdata->regmap, SN_SSC_CONFIG_REG, DP_NUM_LANES_MASK, val); valid_rates = ti_sn_bridge_read_valid_rates(pdata); /* Train until we run out of rates */ for (dp_rate_idx = ti_sn_bridge_calc_min_dp_rate_idx(pdata, bpp); dp_rate_idx < ARRAY_SIZE(ti_sn_bridge_dp_rate_lut); dp_rate_idx++) { if (!(valid_rates & BIT(dp_rate_idx))) continue; ret = ti_sn_link_training(pdata, dp_rate_idx, &last_err_str); if (!ret) break; } if (ret) { DRM_DEV_ERROR(pdata->dev, "%s (%d)\n", last_err_str, ret); return; } /* config video parameters */ ti_sn_bridge_set_video_timings(pdata); /* enable video stream */ regmap_update_bits(pdata->regmap, SN_ENH_FRAME_REG, VSTREAM_ENABLE, VSTREAM_ENABLE); } static void ti_sn_bridge_atomic_pre_enable(struct drm_bridge *bridge, struct drm_bridge_state *old_bridge_state) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); pm_runtime_get_sync(pdata->dev); if (!pdata->refclk) ti_sn65dsi86_enable_comms(pdata); /* td7: min 100 us after enable before DSI data */ usleep_range(100, 110); } static void ti_sn_bridge_atomic_post_disable(struct drm_bridge *bridge, struct drm_bridge_state *old_bridge_state) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); /* semi auto link training mode OFF */ regmap_write(pdata->regmap, SN_ML_TX_MODE_REG, 0); /* Num lanes to 0 as per power sequencing in data sheet */ regmap_update_bits(pdata->regmap, SN_SSC_CONFIG_REG, DP_NUM_LANES_MASK, 0); /* disable DP PLL */ regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 0); if (!pdata->refclk) ti_sn65dsi86_disable_comms(pdata); pm_runtime_put_sync(pdata->dev); } static enum drm_connector_status ti_sn_bridge_detect(struct drm_bridge *bridge) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); int val = 0; pm_runtime_get_sync(pdata->dev); regmap_read(pdata->regmap, SN_HPD_DISABLE_REG, &val); pm_runtime_put_autosuspend(pdata->dev); return val & HPD_DEBOUNCED_STATE ? connector_status_connected : connector_status_disconnected; } static struct edid *ti_sn_bridge_get_edid(struct drm_bridge *bridge, struct drm_connector *connector) { struct ti_sn65dsi86 *pdata = bridge_to_ti_sn65dsi86(bridge); return drm_get_edid(connector, &pdata->aux.ddc); } static const struct drm_bridge_funcs ti_sn_bridge_funcs = { .attach = ti_sn_bridge_attach, .detach = ti_sn_bridge_detach, .mode_valid = ti_sn_bridge_mode_valid, .get_edid = ti_sn_bridge_get_edid, .detect = ti_sn_bridge_detect, .atomic_pre_enable = ti_sn_bridge_atomic_pre_enable, .atomic_enable = ti_sn_bridge_atomic_enable, .atomic_disable = ti_sn_bridge_atomic_disable, .atomic_post_disable = ti_sn_bridge_atomic_post_disable, .atomic_reset = drm_atomic_helper_bridge_reset, .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, }; static void ti_sn_bridge_parse_lanes(struct ti_sn65dsi86 *pdata, struct device_node *np) { u32 lane_assignments[SN_MAX_DP_LANES] = { 0, 1, 2, 3 }; u32 lane_polarities[SN_MAX_DP_LANES] = { }; struct device_node *endpoint; u8 ln_assign = 0; u8 ln_polrs = 0; int dp_lanes; int i; /* * Read config from the device tree about lane remapping and lane * polarities. These are optional and we assume identity map and * normal polarity if nothing is specified. It's OK to specify just * data-lanes but not lane-polarities but not vice versa. * * Error checking is light (we just make sure we don't crash or * buffer overrun) and we assume dts is well formed and specifying * mappings that the hardware supports. */ endpoint = of_graph_get_endpoint_by_regs(np, 1, -1); dp_lanes = drm_of_get_data_lanes_count(endpoint, 1, SN_MAX_DP_LANES); if (dp_lanes > 0) { of_property_read_u32_array(endpoint, "data-lanes", lane_assignments, dp_lanes); of_property_read_u32_array(endpoint, "lane-polarities", lane_polarities, dp_lanes); } else { dp_lanes = SN_MAX_DP_LANES; } of_node_put(endpoint); /* * Convert into register format. Loop over all lanes even if * data-lanes had fewer elements so that we nicely initialize * the LN_ASSIGN register. */ for (i = SN_MAX_DP_LANES - 1; i >= 0; i--) { ln_assign = ln_assign << LN_ASSIGN_WIDTH | lane_assignments[i]; ln_polrs = ln_polrs << 1 | lane_polarities[i]; } /* Stash in our struct for when we power on */ pdata->dp_lanes = dp_lanes; pdata->ln_assign = ln_assign; pdata->ln_polrs = ln_polrs; } static int ti_sn_bridge_parse_dsi_host(struct ti_sn65dsi86 *pdata) { struct device_node *np = pdata->dev->of_node; pdata->host_node = of_graph_get_remote_node(np, 0, 0); if (!pdata->host_node) { DRM_ERROR("remote dsi host node not found\n"); return -ENODEV; } return 0; } static int ti_sn_bridge_probe(struct auxiliary_device *adev, const struct auxiliary_device_id *id) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); struct device_node *np = pdata->dev->of_node; int ret; pdata->next_bridge = devm_drm_of_get_bridge(pdata->dev, np, 1, 0); if (IS_ERR(pdata->next_bridge)) return dev_err_probe(pdata->dev, PTR_ERR(pdata->next_bridge), "failed to create panel bridge\n"); ti_sn_bridge_parse_lanes(pdata, np); ret = ti_sn_bridge_parse_dsi_host(pdata); if (ret) return ret; pdata->bridge.funcs = &ti_sn_bridge_funcs; pdata->bridge.of_node = np; pdata->bridge.type = pdata->next_bridge->type == DRM_MODE_CONNECTOR_DisplayPort ? DRM_MODE_CONNECTOR_DisplayPort : DRM_MODE_CONNECTOR_eDP; if (pdata->bridge.type == DRM_MODE_CONNECTOR_DisplayPort) pdata->bridge.ops = DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_DETECT; drm_bridge_add(&pdata->bridge); ret = ti_sn_attach_host(pdata); if (ret) { dev_err_probe(pdata->dev, ret, "failed to attach dsi host\n"); goto err_remove_bridge; } return 0; err_remove_bridge: drm_bridge_remove(&pdata->bridge); return ret; } static void ti_sn_bridge_remove(struct auxiliary_device *adev) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); if (!pdata) return; drm_bridge_remove(&pdata->bridge); of_node_put(pdata->host_node); } static const struct auxiliary_device_id ti_sn_bridge_id_table[] = { { .name = "ti_sn65dsi86.bridge", }, {}, }; static struct auxiliary_driver ti_sn_bridge_driver = { .name = "bridge", .probe = ti_sn_bridge_probe, .remove = ti_sn_bridge_remove, .id_table = ti_sn_bridge_id_table, }; /* ----------------------------------------------------------------------------- * PWM Controller */ #if defined(CONFIG_PWM) static int ti_sn_pwm_pin_request(struct ti_sn65dsi86 *pdata) { return atomic_xchg(&pdata->pwm_pin_busy, 1) ? -EBUSY : 0; } static void ti_sn_pwm_pin_release(struct ti_sn65dsi86 *pdata) { atomic_set(&pdata->pwm_pin_busy, 0); } static struct ti_sn65dsi86 *pwm_chip_to_ti_sn_bridge(struct pwm_chip *chip) { return container_of(chip, struct ti_sn65dsi86, pchip); } static int ti_sn_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) { struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip); return ti_sn_pwm_pin_request(pdata); } static void ti_sn_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip); ti_sn_pwm_pin_release(pdata); } /* * Limitations: * - The PWM signal is not driven when the chip is powered down, or in its * reset state and the driver does not implement the "suspend state" * described in the documentation. In order to save power, state->enabled is * interpreted as denoting if the signal is expected to be valid, and is used * to determine if the chip needs to be kept powered. * - Changing both period and duty_cycle is not done atomically, neither is the * multi-byte register updates, so the output might briefly be undefined * during update. */ static int ti_sn_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip); unsigned int pwm_en_inv; unsigned int backlight; unsigned int pre_div; unsigned int scale; u64 period_max; u64 period; int ret; if (!pdata->pwm_enabled) { ret = pm_runtime_get_sync(pdata->dev); if (ret < 0) { pm_runtime_put_sync(pdata->dev); return ret; } } if (state->enabled) { if (!pdata->pwm_enabled) { /* * The chip might have been powered down while we * didn't hold a PM runtime reference, so mux in the * PWM function on the GPIO pin again. */ ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG, SN_GPIO_MUX_MASK << (2 * SN_PWM_GPIO_IDX), SN_GPIO_MUX_SPECIAL << (2 * SN_PWM_GPIO_IDX)); if (ret) { dev_err(pdata->dev, "failed to mux in PWM function\n"); goto out; } } /* * Per the datasheet the PWM frequency is given by: * * REFCLK_FREQ * PWM_FREQ = ----------------------------------- * PWM_PRE_DIV * BACKLIGHT_SCALE + 1 * * However, after careful review the author is convinced that * the documentation has lost some parenthesis around * "BACKLIGHT_SCALE + 1". * * With the period T_pwm = 1/PWM_FREQ this can be written: * * T_pwm * REFCLK_FREQ = PWM_PRE_DIV * (BACKLIGHT_SCALE + 1) * * In order to keep BACKLIGHT_SCALE within its 16 bits, * PWM_PRE_DIV must be: * * T_pwm * REFCLK_FREQ * PWM_PRE_DIV >= ------------------------- * BACKLIGHT_SCALE_MAX + 1 * * To simplify the search and to favour higher resolution of * the duty cycle over accuracy of the period, the lowest * possible PWM_PRE_DIV is used. Finally the scale is * calculated as: * * T_pwm * REFCLK_FREQ * BACKLIGHT_SCALE = ---------------------- - 1 * PWM_PRE_DIV * * Here T_pwm is represented in seconds, so appropriate scaling * to nanoseconds is necessary. */ /* Minimum T_pwm is 1 / REFCLK_FREQ */ if (state->period <= NSEC_PER_SEC / pdata->pwm_refclk_freq) { ret = -EINVAL; goto out; } /* * Maximum T_pwm is 255 * (65535 + 1) / REFCLK_FREQ * Limit period to this to avoid overflows */ period_max = div_u64((u64)NSEC_PER_SEC * 255 * (65535 + 1), pdata->pwm_refclk_freq); period = min(state->period, period_max); pre_div = DIV64_U64_ROUND_UP(period * pdata->pwm_refclk_freq, (u64)NSEC_PER_SEC * (BACKLIGHT_SCALE_MAX + 1)); scale = div64_u64(period * pdata->pwm_refclk_freq, (u64)NSEC_PER_SEC * pre_div) - 1; /* * The documentation has the duty ratio given as: * * duty BACKLIGHT * ------- = --------------------- * period BACKLIGHT_SCALE + 1 * * Solve for BACKLIGHT, substituting BACKLIGHT_SCALE according * to definition above and adjusting for nanosecond * representation of duty cycle gives us: */ backlight = div64_u64(state->duty_cycle * pdata->pwm_refclk_freq, (u64)NSEC_PER_SEC * pre_div); if (backlight > scale) backlight = scale; ret = regmap_write(pdata->regmap, SN_PWM_PRE_DIV_REG, pre_div); if (ret) { dev_err(pdata->dev, "failed to update PWM_PRE_DIV\n"); goto out; } ti_sn65dsi86_write_u16(pdata, SN_BACKLIGHT_SCALE_REG, scale); ti_sn65dsi86_write_u16(pdata, SN_BACKLIGHT_REG, backlight); } pwm_en_inv = FIELD_PREP(SN_PWM_EN_MASK, state->enabled) | FIELD_PREP(SN_PWM_INV_MASK, state->polarity == PWM_POLARITY_INVERSED); ret = regmap_write(pdata->regmap, SN_PWM_EN_INV_REG, pwm_en_inv); if (ret) { dev_err(pdata->dev, "failed to update PWM_EN/PWM_INV\n"); goto out; } pdata->pwm_enabled = state->enabled; out: if (!pdata->pwm_enabled) pm_runtime_put_sync(pdata->dev); return ret; } static int ti_sn_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { struct ti_sn65dsi86 *pdata = pwm_chip_to_ti_sn_bridge(chip); unsigned int pwm_en_inv; unsigned int pre_div; u16 backlight; u16 scale; int ret; ret = regmap_read(pdata->regmap, SN_PWM_EN_INV_REG, &pwm_en_inv); if (ret) return 0; ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_SCALE_REG, &scale); if (ret) return 0; ret = ti_sn65dsi86_read_u16(pdata, SN_BACKLIGHT_REG, &backlight); if (ret) return 0; ret = regmap_read(pdata->regmap, SN_PWM_PRE_DIV_REG, &pre_div); if (ret) return 0; state->enabled = FIELD_GET(SN_PWM_EN_MASK, pwm_en_inv); if (FIELD_GET(SN_PWM_INV_MASK, pwm_en_inv)) state->polarity = PWM_POLARITY_INVERSED; else state->polarity = PWM_POLARITY_NORMAL; state->period = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pre_div * (scale + 1), pdata->pwm_refclk_freq); state->duty_cycle = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pre_div * backlight, pdata->pwm_refclk_freq); if (state->duty_cycle > state->period) state->duty_cycle = state->period; return 0; } static const struct pwm_ops ti_sn_pwm_ops = { .request = ti_sn_pwm_request, .free = ti_sn_pwm_free, .apply = ti_sn_pwm_apply, .get_state = ti_sn_pwm_get_state, .owner = THIS_MODULE, }; static int ti_sn_pwm_probe(struct auxiliary_device *adev, const struct auxiliary_device_id *id) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); pdata->pchip.dev = pdata->dev; pdata->pchip.ops = &ti_sn_pwm_ops; pdata->pchip.npwm = 1; pdata->pchip.of_xlate = of_pwm_single_xlate; pdata->pchip.of_pwm_n_cells = 1; return pwmchip_add(&pdata->pchip); } static void ti_sn_pwm_remove(struct auxiliary_device *adev) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); pwmchip_remove(&pdata->pchip); if (pdata->pwm_enabled) pm_runtime_put_sync(pdata->dev); } static const struct auxiliary_device_id ti_sn_pwm_id_table[] = { { .name = "ti_sn65dsi86.pwm", }, {}, }; static struct auxiliary_driver ti_sn_pwm_driver = { .name = "pwm", .probe = ti_sn_pwm_probe, .remove = ti_sn_pwm_remove, .id_table = ti_sn_pwm_id_table, }; static int __init ti_sn_pwm_register(void) { return auxiliary_driver_register(&ti_sn_pwm_driver); } static void ti_sn_pwm_unregister(void) { auxiliary_driver_unregister(&ti_sn_pwm_driver); } #else static inline int ti_sn_pwm_pin_request(struct ti_sn65dsi86 *pdata) { return 0; } static inline void ti_sn_pwm_pin_release(struct ti_sn65dsi86 *pdata) {} static inline int ti_sn_pwm_register(void) { return 0; } static inline void ti_sn_pwm_unregister(void) {} #endif /* ----------------------------------------------------------------------------- * GPIO Controller */ #if defined(CONFIG_OF_GPIO) static int tn_sn_bridge_of_xlate(struct gpio_chip *chip, const struct of_phandle_args *gpiospec, u32 *flags) { if (WARN_ON(gpiospec->args_count < chip->of_gpio_n_cells)) return -EINVAL; if (gpiospec->args[0] > chip->ngpio || gpiospec->args[0] < 1) return -EINVAL; if (flags) *flags = gpiospec->args[1]; return gpiospec->args[0] - SN_GPIO_PHYSICAL_OFFSET; } static int ti_sn_bridge_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); /* * We already have to keep track of the direction because we use * that to figure out whether we've powered the device. We can * just return that rather than (maybe) powering up the device * to ask its direction. */ return test_bit(offset, pdata->gchip_output) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN; } static int ti_sn_bridge_gpio_get(struct gpio_chip *chip, unsigned int offset) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); unsigned int val; int ret; /* * When the pin is an input we don't forcibly keep the bridge * powered--we just power it on to read the pin. NOTE: part of * the reason this works is that the bridge defaults (when * powered back on) to all 4 GPIOs being configured as GPIO input. * Also note that if something else is keeping the chip powered the * pm_runtime functions are lightweight increments of a refcount. */ pm_runtime_get_sync(pdata->dev); ret = regmap_read(pdata->regmap, SN_GPIO_IO_REG, &val); pm_runtime_put_autosuspend(pdata->dev); if (ret) return ret; return !!(val & BIT(SN_GPIO_INPUT_SHIFT + offset)); } static void ti_sn_bridge_gpio_set(struct gpio_chip *chip, unsigned int offset, int val) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); int ret; if (!test_bit(offset, pdata->gchip_output)) { dev_err(pdata->dev, "Ignoring GPIO set while input\n"); return; } val &= 1; ret = regmap_update_bits(pdata->regmap, SN_GPIO_IO_REG, BIT(SN_GPIO_OUTPUT_SHIFT + offset), val << (SN_GPIO_OUTPUT_SHIFT + offset)); if (ret) dev_warn(pdata->dev, "Failed to set bridge GPIO %u: %d\n", offset, ret); } static int ti_sn_bridge_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); int shift = offset * 2; int ret; if (!test_and_clear_bit(offset, pdata->gchip_output)) return 0; ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG, SN_GPIO_MUX_MASK << shift, SN_GPIO_MUX_INPUT << shift); if (ret) { set_bit(offset, pdata->gchip_output); return ret; } /* * NOTE: if nobody else is powering the device this may fully power * it off and when it comes back it will have lost all state, but * that's OK because the default is input and we're now an input. */ pm_runtime_put_autosuspend(pdata->dev); return 0; } static int ti_sn_bridge_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, int val) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); int shift = offset * 2; int ret; if (test_and_set_bit(offset, pdata->gchip_output)) return 0; pm_runtime_get_sync(pdata->dev); /* Set value first to avoid glitching */ ti_sn_bridge_gpio_set(chip, offset, val); /* Set direction */ ret = regmap_update_bits(pdata->regmap, SN_GPIO_CTRL_REG, SN_GPIO_MUX_MASK << shift, SN_GPIO_MUX_OUTPUT << shift); if (ret) { clear_bit(offset, pdata->gchip_output); pm_runtime_put_autosuspend(pdata->dev); } return ret; } static int ti_sn_bridge_gpio_request(struct gpio_chip *chip, unsigned int offset) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); if (offset == SN_PWM_GPIO_IDX) return ti_sn_pwm_pin_request(pdata); return 0; } static void ti_sn_bridge_gpio_free(struct gpio_chip *chip, unsigned int offset) { struct ti_sn65dsi86 *pdata = gpiochip_get_data(chip); /* We won't keep pm_runtime if we're input, so switch there on free */ ti_sn_bridge_gpio_direction_input(chip, offset); if (offset == SN_PWM_GPIO_IDX) ti_sn_pwm_pin_release(pdata); } static const char * const ti_sn_bridge_gpio_names[SN_NUM_GPIOS] = { "GPIO1", "GPIO2", "GPIO3", "GPIO4" }; static int ti_sn_gpio_probe(struct auxiliary_device *adev, const struct auxiliary_device_id *id) { struct ti_sn65dsi86 *pdata = dev_get_drvdata(adev->dev.parent); int ret; /* Only init if someone is going to use us as a GPIO controller */ if (!of_property_read_bool(pdata->dev->of_node, "gpio-controller")) return 0; pdata->gchip.label = dev_name(pdata->dev); pdata->gchip.parent = pdata->dev; pdata->gchip.owner = THIS_MODULE; pdata->gchip.of_xlate = tn_sn_bridge_of_xlate; pdata->gchip.of_gpio_n_cells = 2; pdata->gchip.request = ti_sn_bridge_gpio_request; pdata->gchip.free = ti_sn_bridge_gpio_free; pdata->gchip.get_direction = ti_sn_bridge_gpio_get_direction; pdata->gchip.direction_input = ti_sn_bridge_gpio_direction_input; pdata->gchip.direction_output = ti_sn_bridge_gpio_direction_output; pdata->gchip.get = ti_sn_bridge_gpio_get; pdata->gchip.set = ti_sn_bridge_gpio_set; pdata->gchip.can_sleep = true; pdata->gchip.names = ti_sn_bridge_gpio_names; pdata->gchip.ngpio = SN_NUM_GPIOS; pdata->gchip.base = -1; ret = devm_gpiochip_add_data(&adev->dev, &pdata->gchip, pdata); if (ret) dev_err(pdata->dev, "can't add gpio chip\n"); return ret; } static const struct auxiliary_device_id ti_sn_gpio_id_table[] = { { .name = "ti_sn65dsi86.gpio", }, {}, }; MODULE_DEVICE_TABLE(auxiliary, ti_sn_gpio_id_table); static struct auxiliary_driver ti_sn_gpio_driver = { .name = "gpio", .probe = ti_sn_gpio_probe, .id_table = ti_sn_gpio_id_table, }; static int __init ti_sn_gpio_register(void) { return auxiliary_driver_register(&ti_sn_gpio_driver); } static void ti_sn_gpio_unregister(void) { auxiliary_driver_unregister(&ti_sn_gpio_driver); } #else static inline int ti_sn_gpio_register(void) { return 0; } static inline void ti_sn_gpio_unregister(void) {} #endif /* ----------------------------------------------------------------------------- * Probe & Remove */ static void ti_sn65dsi86_runtime_disable(void *data) { pm_runtime_dont_use_autosuspend(data); pm_runtime_disable(data); } static int ti_sn65dsi86_parse_regulators(struct ti_sn65dsi86 *pdata) { unsigned int i; const char * const ti_sn_bridge_supply_names[] = { "vcca", "vcc", "vccio", "vpll", }; for (i = 0; i < SN_REGULATOR_SUPPLY_NUM; i++) pdata->supplies[i].supply = ti_sn_bridge_supply_names[i]; return devm_regulator_bulk_get(pdata->dev, SN_REGULATOR_SUPPLY_NUM, pdata->supplies); } static int ti_sn65dsi86_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct ti_sn65dsi86 *pdata; int ret; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { DRM_ERROR("device doesn't support I2C\n"); return -ENODEV; } pdata = devm_kzalloc(dev, sizeof(struct ti_sn65dsi86), GFP_KERNEL); if (!pdata) return -ENOMEM; dev_set_drvdata(dev, pdata); pdata->dev = dev; mutex_init(&pdata->comms_mutex); pdata->regmap = devm_regmap_init_i2c(client, &ti_sn65dsi86_regmap_config); if (IS_ERR(pdata->regmap)) return dev_err_probe(dev, PTR_ERR(pdata->regmap), "regmap i2c init failed\n"); pdata->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW); if (IS_ERR(pdata->enable_gpio)) return dev_err_probe(dev, PTR_ERR(pdata->enable_gpio), "failed to get enable gpio from DT\n"); ret = ti_sn65dsi86_parse_regulators(pdata); if (ret) return dev_err_probe(dev, ret, "failed to parse regulators\n"); pdata->refclk = devm_clk_get_optional(dev, "refclk"); if (IS_ERR(pdata->refclk)) return dev_err_probe(dev, PTR_ERR(pdata->refclk), "failed to get reference clock\n"); pm_runtime_enable(dev); pm_runtime_set_autosuspend_delay(pdata->dev, 500); pm_runtime_use_autosuspend(pdata->dev); ret = devm_add_action_or_reset(dev, ti_sn65dsi86_runtime_disable, dev); if (ret) return ret; ti_sn65dsi86_debugfs_init(pdata); /* * Break ourselves up into a collection of aux devices. The only real * motiviation here is to solve the chicken-and-egg problem of probe * ordering. The bridge wants the panel to be there when it probes. * The panel wants its HPD GPIO (provided by sn65dsi86 on some boards) * when it probes. The panel and maybe backlight might want the DDC * bus or the pwm_chip. Having sub-devices allows the some sub devices * to finish probing even if others return -EPROBE_DEFER and gets us * around the problems. */ if (IS_ENABLED(CONFIG_OF_GPIO)) { ret = ti_sn65dsi86_add_aux_device(pdata, &pdata->gpio_aux, "gpio"); if (ret) return ret; } if (IS_ENABLED(CONFIG_PWM)) { ret = ti_sn65dsi86_add_aux_device(pdata, &pdata->pwm_aux, "pwm"); if (ret) return ret; } /* * NOTE: At the end of the AUX channel probe we'll add the aux device * for the bridge. This is because the bridge can't be used until the * AUX channel is there and this is a very simple solution to the * dependency problem. */ return ti_sn65dsi86_add_aux_device(pdata, &pdata->aux_aux, "aux"); } static struct i2c_device_id ti_sn65dsi86_id[] = { { "ti,sn65dsi86", 0}, {}, }; MODULE_DEVICE_TABLE(i2c, ti_sn65dsi86_id); static const struct of_device_id ti_sn65dsi86_match_table[] = { {.compatible = "ti,sn65dsi86"}, {}, }; MODULE_DEVICE_TABLE(of, ti_sn65dsi86_match_table); static struct i2c_driver ti_sn65dsi86_driver = { .driver = { .name = "ti_sn65dsi86", .of_match_table = ti_sn65dsi86_match_table, .pm = &ti_sn65dsi86_pm_ops, }, .probe = ti_sn65dsi86_probe, .id_table = ti_sn65dsi86_id, }; static int __init ti_sn65dsi86_init(void) { int ret; ret = i2c_add_driver(&ti_sn65dsi86_driver); if (ret) return ret; ret = ti_sn_gpio_register(); if (ret) goto err_main_was_registered; ret = ti_sn_pwm_register(); if (ret) goto err_gpio_was_registered; ret = auxiliary_driver_register(&ti_sn_aux_driver); if (ret) goto err_pwm_was_registered; ret = auxiliary_driver_register(&ti_sn_bridge_driver); if (ret) goto err_aux_was_registered; return 0; err_aux_was_registered: auxiliary_driver_unregister(&ti_sn_aux_driver); err_pwm_was_registered: ti_sn_pwm_unregister(); err_gpio_was_registered: ti_sn_gpio_unregister(); err_main_was_registered: i2c_del_driver(&ti_sn65dsi86_driver); return ret; } module_init(ti_sn65dsi86_init); static void __exit ti_sn65dsi86_exit(void) { auxiliary_driver_unregister(&ti_sn_bridge_driver); auxiliary_driver_unregister(&ti_sn_aux_driver); ti_sn_pwm_unregister(); ti_sn_gpio_unregister(); i2c_del_driver(&ti_sn65dsi86_driver); } module_exit(ti_sn65dsi86_exit); MODULE_AUTHOR("Sandeep Panda "); MODULE_DESCRIPTION("sn65dsi86 DSI to eDP bridge driver"); MODULE_LICENSE("GPL v2");