[PATCH 2/8] ARM: iop32x: request and issue reset using gpio

Linus Walleij linus.walleij at linaro.org
Mon Sep 9 11:40:23 EDT 2013


As the IOP GPIO driver supports gpiolib we can use the standard
GPIO calls to issue a reset of the machine instead of using the
custom gpio_line_set/config calls. Also request the GPIO when
initializing the machine.

Cc: Lennert Buytenhek <kernel at wantstofly.org>
Cc: Dan Williams <dan.j.williams at intel.com>
Cc: Mikael Pettersson <mikpe at it.uu.se>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
 arch/arm/mach-iop32x/n2100.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c
index 0691443..cd199c1 100644
--- a/arch/arm/mach-iop32x/n2100.c
+++ b/arch/arm/mach-iop32x/n2100.c
@@ -30,6 +30,7 @@
 #include <linux/platform_device.h>
 #include <linux/reboot.h>
 #include <linux/io.h>
+#include <linux/gpio.h>
 #include <mach/hardware.h>
 #include <asm/irq.h>
 #include <asm/mach/arch.h>
@@ -288,8 +289,14 @@ static void n2100_power_off(void)
 
 static void n2100_restart(enum reboot_mode mode, const char *cmd)
 {
-	gpio_line_set(N2100_HARDWARE_RESET, GPIO_LOW);
-	gpio_line_config(N2100_HARDWARE_RESET, GPIO_OUT);
+	int ret;
+
+	ret = gpio_direction_output(N2100_HARDWARE_RESET, 0);
+	if (ret) {
+		pr_crit("could not drive reset GPIO low\n");
+		return;
+	}
+	/* Wait for reset to happen */
 	while (1)
 		;
 }
@@ -311,6 +318,8 @@ static void power_button_poll(unsigned long dummy)
 
 static void __init n2100_init_machine(void)
 {
+	int ret;
+
 	platform_device_register(&iop3xx_i2c0_device);
 	platform_device_register(&n2100_flash_device);
 	platform_device_register(&n2100_serial_device);
@@ -326,6 +335,10 @@ static void __init n2100_init_machine(void)
 	power_button_poll_timer.function = power_button_poll;
 	power_button_poll_timer.expires = jiffies + (HZ / 10);
 	add_timer(&power_button_poll_timer);
+
+	ret = gpio_request(N2100_HARDWARE_RESET, "reset");
+	if (ret)
+		pr_err("could not request reset GPIO\n");
 }
 
 MACHINE_START(N2100, "Thecus N2100")
-- 
1.8.3.1




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