Buffalo Linkstation / KuroBox and their variants need magic command
sending to UART1 to power-off.
Power driver linkstation-reset implements the magic command and I/O
routine, which come from files listed below:
- arch/arm/mach-orion5x/kurobox_pro-setup.c
- arch/arm/mach-orion5x/terastation_pro2-setup.c
To: Sebastian Reichel <sre@xxxxxxxxxx>
Cc: Andrew Lunn <andrew@xxxxxxx>
Cc: Martin Michlmayr <tbm@xxxxxxxxxx>
Cc: Sylver Bruneau <sylver.bruneau@xxxxxxxxxxxxxx>
Cc: Herbert Valerio Riedel <hvr@xxxxxxx>
Cc: Ryan Tandy <ryan@xxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Reported-by: Ryan Tandy <ryan@xxxxxxxxx>
Tested-by: Ryan Tandy <ryan@xxxxxxxxx>
Signed-off-by: Roger Shimizu <rogershimizu@xxxxxxxxx>
---
drivers/power/reset/Kconfig | 10 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/linkstation-reset.c | 269 ++++++++++++++++++++++++++++++++
3 files changed, 280 insertions(+)
create mode 100644 drivers/power/reset/linkstation-reset.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index c74c3f67b8da..77c44cad7ece 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -98,6 +98,16 @@ config POWER_RESET_IMX
say N here or disable in dts to make sure pm_power_off never be
overwrote wrongly by this driver.
+config POWER_RESET_LINKSTATION
+ bool "Buffalo Linkstation and its variants reset driver"
+ depends on OF_GPIO && PLAT_ORION
+ help
+ This driver supports power off Buffalo Linkstation / KuroBox Pro
+ NAS and their variants by sending commands to the micro-controller
+ which controls the main power.
+
+ Say Y if you have a Buffalo Linkstation / KuroBox Pro NAS.
+
config POWER_RESET_MSM
bool "Qualcomm MSM power-off driver"
depends on ARCH_QCOM
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 1be307c7fc25..692ba6417cfb 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o
obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o
obj-$(CONFIG_POWER_RESET_IMX) += imx-snvs-poweroff.o
+obj-$(CONFIG_POWER_RESET_LINKSTATION) += linkstation-reset.o
obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o
obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
diff --git a/drivers/power/reset/linkstation-reset.c b/drivers/power/reset/linkstation-reset.c
new file mode 100644
index 000000000000..4390495dfe0e
--- /dev/null
+++ b/drivers/power/reset/linkstation-reset.c
@@ -0,0 +1,269 @@
+/*
+ * Buffalo Linkstation power reset driver.
+ * It may also be used on following devices:
+ * - KuroBox Pro
+ * - Buffalo Linkstation Pro (LS-GL)
+ * - Buffalo Terastation Pro II/Live
+ * - Buffalo Linkstation Duo (LS-WTGL)
+ * - Buffalo Linkstation Mini (LS-WSGL)
+ *
+ * Copyright (C) 2016 Roger Shimizu <rogershimizu@xxxxxxxxx>
+ *
+ * Based on the code from:
+ *
+ * Copyright (C) 2012 Andrew Lunn <andrew@xxxxxxx>
+ * Copyright (C) 2009 Martin Michlmayr <tbm@xxxxxxxxxx>
+ * Copyright (C) 2008 Byron Bradley <byron.bbradley@xxxxxxxxx>
+ * Copyright (C) 2008 Sylver Bruneau <sylver.bruneau@xxxxxxxxxxxxxx>
+ * Copyright (C) 2007 Herbert Valerio Riedel <hvr@xxxxxxx>
+ *
+ * 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>
+#include <linux/delay.h>
+
+#define UART1_REG(x) (base + ((UART_##x) << 2))
+#define MICON_CMD_SIZE 4
+
+/* 4-byte magic hello command to UART1-attached microcontroller */
+static const unsigned char linkstation_micon_magic[] = {
+ 0x1b,
+ 0x00,
+ 0x07,
+ 0x00
+};
+
+/* for each row, first byte is the size of command */
+static const unsigned char linkstation_power_off_cmd[][MICON_CMD_SIZE] = {
+ { 3, 0x01, 0x35, 0x00},
+ { 2, 0x00, 0x0c},
+ { 2, 0x00, 0x06},
+ {}
+};
+
+struct reset_cfg {
+ u32 baud;
+ const unsigned char *magic;
+ const unsigned char (*cmd)[MICON_CMD_SIZE];
+};
+
+static const struct reset_cfg linkstation_power_off_cfg = {
+ .baud = 38400,
+ .magic = linkstation_micon_magic,
+ .cmd = linkstation_power_off_cmd,
+};
+
+static const struct of_device_id linkstation_reset_of_match_table[] = {
+ { .compatible = "linkstation,power-off",
+ .data = &linkstation_power_off_cfg,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, linkstation_reset_of_match_table);
+
+static int uart1_micon_read(void *base, unsigned char *buf, int count)
+{
+ int i;
+ int timeout;
+
+ for (i = 0; i < count; i++) {
+ timeout = 10;
+
+ while (!(readl(UART1_REG(LSR)) & UART_LSR_DR)) {
+ if (--timeout == 0)
+ break;
+ udelay(1000);
+ }
+
+ if (timeout == 0)
+ break;
+ buf[i] = readl(UART1_REG(RX));
+ }
+
+ /* return read bytes */
+ return i;
+}
+
+static int uart1_micon_write(void *base, const unsigned char *buf, int count)
+{
+ int i = 0;
+
+ while (count--) {
+ while (!(readl(UART1_REG(LSR)) & UART_LSR_THRE))
+ barrier();
+ writel(buf[i++], UART1_REG(TX));
+ }
+
+ return 0;
+}
+
+int uart1_micon_send(void *base, const unsigned char *data, int count)
+{
+ int i;
+ unsigned char checksum = 0;
+ unsigned char recv_buf[40];
+ unsigned char send_buf[40];
+ unsigned char correct_ack[3];
+ int retry = 2;
+
+ /* Generate checksum */
+ for (i = 0; i < count; i++)
+ checksum -= data[i];
+
+ do {
+ /* Send data */
+ uart1_micon_write(base, data, count);
+
+ /* send checksum */
+ uart1_micon_write(base, &checksum, 1);
+
+ if (uart1_micon_read(base, recv_buf, sizeof(recv_buf)) <= 3) {
+ printk(KERN_ERR ">%s: receive failed.\n", __func__);
+
+ /* send preamble to clear the receive buffer */
+ memset(&send_buf, 0xff, sizeof(send_buf));
+ uart1_micon_write(base, send_buf, sizeof(send_buf));
+
+ /* make dummy reads */
+ mdelay(100);
+ uart1_micon_read(base, recv_buf, sizeof(recv_buf));
+ } else {
+ /* Generate expected ack */
+ correct_ack[0] = 0x01;
+ correct_ack[1] = data[1];
+ correct_ack[2] = 0x00;
+
+ /* checksum Check */
+ if ((recv_buf[0] + recv_buf[1] + recv_buf[2] +
+ recv_buf[3]) & 0xFF) {
+ printk(KERN_ERR ">%s: Checksum Error : "
+ "Received data[%02x, %02x, %02x, %02x]"
+ "\n", __func__, recv_buf[0],
+ recv_buf[1], recv_buf[2], recv_buf[3]);
+ } else {
+ /* Check Received Data */
+ if (correct_ack[0] == recv_buf[0] &&
+ correct_ack[1] == recv_buf[1] &&
+ correct_ack[2] == recv_buf[2]) {
+ /* Interval for next command */
+ mdelay(10);
+
+ /* Receive ACK */
+ return 0;
+ }
+ }
+ /* Received NAK or illegal Data */
+ printk(KERN_ERR ">%s: Error : NAK or Illegal Data "
+ "Received\n", __func__);
+ }
+ } while (retry--);
+
+ /* Interval for next command */
+ mdelay(10);
+
+ return -1;
+}
+
+static void __iomem *base;
+static unsigned long tclk;
+static const struct reset_cfg *cfg;
+
+static void linkstation_reset(void)
+{
+ const unsigned divisor = ((tclk + (8 * cfg->baud)) / (16 * cfg->baud));
+ int i;
+
+ 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(cfg->magic[0], UART1_REG(LCR));
+ writel(cfg->magic[1], UART1_REG(IER));
+ writel(cfg->magic[2], UART1_REG(FCR));
+ writel(cfg->magic[3], UART1_REG(MCR));
+
+ /* send the power-off command to PIC */
+ for(i = 0; cfg->cmd[i][0] > 0; i ++) {
+ /* [0] is size of the command; command starts from [1] */
+ uart1_micon_send(base, &(cfg->cmd[i][1]), cfg->cmd[i][0]);
+ }
+}
+
+static int linkstation_reset_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(linkstation_reset_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 = linkstation_reset;
+
+ return 0;
+}
+
+static int linkstation_reset_remove(struct platform_device *pdev)
+{
+ pm_power_off = NULL;
+ return 0;
+}
+
+static struct platform_driver linkstation_reset_driver = {
+ .probe = linkstation_reset_probe,
+ .remove = linkstation_reset_remove,
+ .driver = {
+ .name = "linkstation_reset",
+ .of_match_table = of_match_ptr(linkstation_reset_of_match_table),
+ },
+};
+
+module_platform_driver(linkstation_reset_driver);
+
+MODULE_AUTHOR("Roger Shimizu <rogershimizu@xxxxxxxxx>");
+MODULE_DESCRIPTION("Linkstation Reset driver");
+MODULE_LICENSE("GPL v2");
--
2.11.0
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