[PATCH 1/4] Power: Reset: Driver to turn QNAP board power off.
Andrew Lunn
andrew at lunn.ch
Fri Dec 28 07:25:09 EST 2012
From: Andrew Lunn <andrew.lunn at ruag.com>
The QNAP NAS boxes have a microcontroller attached to the SoCs second
serial port. By sending it a simple command, it will turn the power
for the board off. This driver registers a function for pm_power_off
to send such a command.
Signed-off-by: Andrew Lunn <andrew at lunn.ch>
---
.../bindings/power_supply/qnap-poweroff.txt | 14 +++
drivers/power/reset/Kconfig | 9 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/qnap-poweroff.c | 124 ++++++++++++++++++++
4 files changed, 148 insertions(+)
create mode 100644 Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
create mode 100644 drivers/power/reset/qnap-poweroff.c
diff --git a/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt b/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
new file mode 100644
index 0000000..0951952
--- /dev/null
+++ b/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
@@ -0,0 +1,14 @@
+* QNAP Power Off
+
+QNAP NAS devices have a microcontroller controlling the main power
+supply. This microcontroller is connected to UART1 of the Kirkwood and
+Orion5x SoCs. Sending the charactor 'A', at 19200 baud, tells the
+microcontroller to turn the power off. This driver adds a handler to
+pm_power_off which is called to turn the power off.
+
+Required Properties:
+- compatible: Should be "qnap,power-off"
+
+- reg: Address and length of the register set for UART1
+- clocks: tclk clock
+
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 6461b48..6453aac 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -13,3 +13,12 @@ config POWER_RESET_GPIO
This driver supports turning off your board via a GPIO line.
If your board needs a GPIO high/low to power down, say Y and
create a binding in your devicetree.
+
+config POWER_RESET_QNAP
+ bool "QNAP power-off driver"
+ depends on OF_GPIO && POWER_RESET && PLAT_ORION
+ help
+ This driver supports turning off QNAP NAS devices by sending
+ commands to the microcontroller which controls the main power.
+
+ Say Y if you have a QNAP NAS.
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 751488a..c4d3b2d 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
+obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
diff --git a/drivers/power/reset/qnap-poweroff.c b/drivers/power/reset/qnap-poweroff.c
new file mode 100644
index 0000000..ca0b476
--- /dev/null
+++ b/drivers/power/reset/qnap-poweroff.c
@@ -0,0 +1,124 @@
+/*
+ * QNAP Turbo NAS Board power off
+ *
+ * Copyright (C) 2012 Andrew Lunn <andrew at lunn.ch>
+ *
+ * Based on the code from:
+ *
+ * Copyright (C) 2009 Martin Michlmayr <tbm at cyrius.com>
+ * Copyright (C) 2008 Byron Bradley <byron.bbradley at 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))
+
+static void __iomem *base;
+static unsigned long tclk;
+
+static void
+qnap_power_off(void)
+{
+ /* 19200 baud divisor */
+ const unsigned divisor = ((tclk + (8 * 19200)) / (16 * 19200));
+
+ pr_err("%s: triggering power-off...\n", __func__);
+
+ /* hijack UART1 and reset into sane state (19200,8n1) */
+ 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 'A' to PIC */
+ writel('A', UART1_REG(TX));
+}
+
+static int
+qnap_power_off_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct clk *clk;
+ char symname[KSYM_NAME_LEN];
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ dev_err(&pdev->dev, "Missing resource");
+ return -EINVAL;
+ }
+
+ base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (base == NULL) {
+ 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 != NULL) {
+ lookup_symbol_name(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;
+}
+
+static int
+qnap_power_off_remove(struct platform_device *pdev)
+{
+ pm_power_off = NULL;
+
+ return 0;
+}
+
+static const struct of_device_id qnap_power_off_of_match_table[] = {
+ { .compatible = "qnap,power-off", },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, qnap_power_off_of_match_table);
+
+static struct platform_driver qnap_power_off_driver = {
+ .probe = qnap_power_off_probe,
+ .remove = qnap_power_off_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .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 at lunn.ch>");
+MODULE_DESCRIPTION("QNAP Power off driver");
+MODULE_LICENSE("GPLv2+");
--
1.7.10.4
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