[PATCH 2/8 v3] ARM: iop32x: request and issue reset using gpio
From: Linus Walleij <hidden>
Date: 2013-09-13 09:07:29
Also in:
linux-gpio
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
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: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: Lennert Buytenhek <kernel@wantstofly.org> Cc: Dan Williams <redacted> Cc: Mikael Pettersson <redacted> Signed-off-by: Linus Walleij <redacted> --- ChangeLog v2->v3: - Also check machine_is_n2100() so we don't request the GPIOs on any other machine at boot. ChangeLog v1->v2: - Request GPIOs in a separate device_initcall() instead of doing it from machine_init, as the gpio chip is registered after the machine init, what was I thinking about? --- arch/arm/mach-iop32x/n2100.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-iop32x/n2100.c b/arch/arm/mach-iop32x/n2100.c
index 0691443..6bace5b 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) ; }
@@ -308,6 +315,19 @@ static void power_button_poll(unsigned long dummy) add_timer(&power_button_poll_timer); } +static int __init n2100_request_gpios(void) +{ + int ret; + + if (!machine_is_n2100()) + return 0; + + ret = gpio_request(N2100_HARDWARE_RESET, "reset"); + if (ret) + pr_err("could not request reset GPIO\n"); + return 0; +} +device_initcall(n2100_request_gpios); static void __init n2100_init_machine(void) {
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1.8.3.1