133 lines
3.1 KiB
C
133 lines
3.1 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-or-later
|
||
|
/*
|
||
|
* QNAP Turbo NAS Board power off. Can also be used on Synology devices.
|
||
|
*
|
||
|
* Copyright (C) 2012 Andrew Lunn <andrew@lunn.ch>
|
||
|
*
|
||
|
* Based on the code from:
|
||
|
*
|
||
|
* Copyright (C) 2009 Martin Michlmayr <tbm@cyrius.com>
|
||
|
* Copyright (C) 2008 Byron Bradley <byron.bbradley@gmail.com>
|
||
|
*/
|
||
|
|
||
|
#include <linux/kernel.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/platform_device.h>
|
||
|
#include <linux/serial_reg.h>
|
||
|
#include <linux/of.h>
|
||
|
#include <linux/io.h>
|
||
|
#include <linux/clk.h>
|
||
|
|
||
|
#define UART1_REG(x) (base + ((UART_##x) << 2))
|
||
|
|
||
|
struct power_off_cfg {
|
||
|
u32 baud;
|
||
|
char cmd;
|
||
|
};
|
||
|
|
||
|
static const struct power_off_cfg qnap_power_off_cfg = {
|
||
|
.baud = 19200,
|
||
|
.cmd = 'A',
|
||
|
};
|
||
|
|
||
|
static const struct power_off_cfg synology_power_off_cfg = {
|
||
|
.baud = 9600,
|
||
|
.cmd = '1',
|
||
|
};
|
||
|
|
||
|
static const struct of_device_id qnap_power_off_of_match_table[] = {
|
||
|
{ .compatible = "qnap,power-off",
|
||
|
.data = &qnap_power_off_cfg,
|
||
|
},
|
||
|
{ .compatible = "synology,power-off",
|
||
|
.data = &synology_power_off_cfg,
|
||
|
},
|
||
|
{}
|
||
|
};
|
||
|
MODULE_DEVICE_TABLE(of, qnap_power_off_of_match_table);
|
||
|
|
||
|
static void __iomem *base;
|
||
|
static unsigned long tclk;
|
||
|
static const struct power_off_cfg *cfg;
|
||
|
|
||
|
static void qnap_power_off(void)
|
||
|
{
|
||
|
const unsigned divisor = ((tclk + (8 * cfg->baud)) / (16 * cfg->baud));
|
||
|
|
||
|
pr_err("%s: triggering power-off...\n", __func__);
|
||
|
|
||
|
/* hijack UART1 and reset into sane state */
|
||
|
writel(0x83, UART1_REG(LCR));
|
||
|
writel(divisor & 0xff, UART1_REG(DLL));
|
||
|
writel((divisor >> 8) & 0xff, UART1_REG(DLM));
|
||
|
writel(0x03, UART1_REG(LCR));
|
||
|
writel(0x00, UART1_REG(IER));
|
||
|
writel(0x00, UART1_REG(FCR));
|
||
|
writel(0x00, UART1_REG(MCR));
|
||
|
|
||
|
/* send the power-off command to PIC */
|
||
|
writel(cfg->cmd, UART1_REG(TX));
|
||
|
}
|
||
|
|
||
|
static int qnap_power_off_probe(struct platform_device *pdev)
|
||
|
{
|
||
|
struct device_node *np = pdev->dev.of_node;
|
||
|
struct resource *res;
|
||
|
struct clk *clk;
|
||
|
|
||
|
const struct of_device_id *match =
|
||
|
of_match_node(qnap_power_off_of_match_table, np);
|
||
|
cfg = match->data;
|
||
|
|
||
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
if (!res) {
|
||
|
dev_err(&pdev->dev, "Missing resource");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
|
||
|
if (!base) {
|
||
|
dev_err(&pdev->dev, "Unable to map resource");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* We need to know tclk in order to calculate the UART divisor */
|
||
|
clk = devm_clk_get(&pdev->dev, NULL);
|
||
|
if (IS_ERR(clk)) {
|
||
|
dev_err(&pdev->dev, "Clk missing");
|
||
|
return PTR_ERR(clk);
|
||
|
}
|
||
|
|
||
|
tclk = clk_get_rate(clk);
|
||
|
|
||
|
/* Check that nothing else has already setup a handler */
|
||
|
if (pm_power_off) {
|
||
|
dev_err(&pdev->dev, "pm_power_off already claimed for %ps",
|
||
|
pm_power_off);
|
||
|
return -EBUSY;
|
||
|
}
|
||
|
pm_power_off = qnap_power_off;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int qnap_power_off_remove(struct platform_device *pdev)
|
||
|
{
|
||
|
pm_power_off = NULL;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static struct platform_driver qnap_power_off_driver = {
|
||
|
.probe = qnap_power_off_probe,
|
||
|
.remove = qnap_power_off_remove,
|
||
|
.driver = {
|
||
|
.name = "qnap_power_off",
|
||
|
.of_match_table = of_match_ptr(qnap_power_off_of_match_table),
|
||
|
},
|
||
|
};
|
||
|
module_platform_driver(qnap_power_off_driver);
|
||
|
|
||
|
MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
|
||
|
MODULE_DESCRIPTION("QNAP Power off driver");
|
||
|
MODULE_LICENSE("GPL v2");
|