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Release 4.11 drivers/power/reset/qnap-poweroff.c

/*
 * 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>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/serial_reg.h>
#include <linux/kallsyms.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)); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Lunn133100.00%2100.00%
Total133100.00%2100.00%


static int qnap_power_off_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct resource *res; struct clk *clk; char symname[KSYM_NAME_LEN]; 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) { lookup_symbol_name((ulong)pm_power_off, symname); dev_err(&pdev->dev, "pm_power_off already claimed %p %s", pm_power_off, symname); return -EBUSY; } pm_power_off = qnap_power_off; return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Lunn216100.00%2100.00%
Total216100.00%2100.00%


static int qnap_power_off_remove(struct platform_device *pdev) { pm_power_off = NULL; return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Lunn18100.00%1100.00%
Total18100.00%1100.00%

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");

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PersonTokensPropCommitsCommitProp
Andrew Lunn563100.00%3100.00%
Total563100.00%3100.00%
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