[PATCH v2] ARM: iop32x: fix power off handling for the EM7210 board

[PATCH v2] ARM: iop32x: fix power off handling for the EM7210 board

[Linus Walleij]

This board was missed when converting all the others to proper
abstracted GPIO handling. Fix it up the right way by requesting
and driving GPIO line 0 high through gpiolib to power off the
machine.

Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
ChangeLog v1->v2:
- Request the power off and set the power off hook with a
  device_initcall() so we know the GPIO driver is available
  when requesting the line.
- Refer to POWER OFF rather than RESET everywhere.

ARM SoC folks, if you're happy with this fix, please apply it
directly to fixes in the ARM SoC tree.
---
 arch/arm/mach-iop32x/em7210.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-iop32x/em7210.c b/arch/arm/mach-iop32x/em7210.c
index 177cd073a83b..77e1ff057303 100644
--- a/arch/arm/mach-iop32x/em7210.c
+++ b/arch/arm/mach-iop32x/em7210.c
@@ -23,6 +23,7 @@
 #include <linux/mtd/physmap.h>
 #include <linux/platform_device.h>
 #include <linux/i2c.h>
+#include <linux/gpio.h>
 #include <mach/hardware.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -176,11 +177,35 @@ static struct platform_device em7210_serial_device = {
 	.resource	= &em7210_uart_resource,
 };
 
+#define EM7210_HARDWARE_POWER 0
+
 void em7210_power_off(void)
 {
-	*IOP3XX_GPOE &= 0xfe;
-	*IOP3XX_GPOD |= 0x01;
+	int ret;
+
+	ret = gpio_direction_output(EM7210_HARDWARE_POWER, 1);
+	if (ret)
+		pr_crit("could not drive power off GPIO high\n");
+}
+
+static int __init em7210_request_gpios(void)
+{
+	int ret;
+
+	if (!machine_is_em7210())
+		return 0;
+
+	ret = gpio_request(EM7210_HARDWARE_POWER, "power");
+	if (ret) {
+		pr_err("could not request power off GPIO\n");
+		return 0;
+	}
+
+	pm_power_off = em7210_power_off;
+
+	return 0;
 }
+device_initcall(em7210_request_gpios);
 
 static void __init em7210_init_machine(void)
 {
@@ -194,9 +219,6 @@ static void __init em7210_init_machine(void)
 
 	i2c_register_board_info(0, em7210_i2c_devices,
 		ARRAY_SIZE(em7210_i2c_devices));
-
-
-	pm_power_off = em7210_power_off;
 }
 
 MACHINE_START(EM7210, "Lanner EM7210")
-- 
1.8.5.3

[PATCH v2] ARM: iop32x: fix power off handling for the EM7210 board

[Arnaud Patard (Rtp)]

Linus Walleij <linus.walleij@linaro.org> writes:

> This board was missed when converting all the others to proper
> abstracted GPIO handling. Fix it up the right way by requesting
> and driving GPIO line 0 high through gpiolib to power off the
> machine.
>
> Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
> Reported-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
> ChangeLog v1->v2:
> - Request the power off and set the power off hook with a
>   device_initcall() so we know the GPIO driver is available
>   when requesting the line.
> - Refer to POWER OFF rather than RESET everywhere.
>
> ARM SoC folks, if you're happy with this fix, please apply it
> directly to fixes in the ARM SoC tree.
> ---
>  arch/arm/mach-iop32x/em7210.c | 32 +++++++++++++++++++++++++++-----
>  1 file changed, 27 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm/mach-iop32x/em7210.c b/arch/arm/mach-iop32x/em7210.c
> index 177cd073a83b..77e1ff057303 100644
> --- a/arch/arm/mach-iop32x/em7210.c
> +++ b/arch/arm/mach-iop32x/em7210.c
> @@ -23,6 +23,7 @@
>  #include <linux/mtd/physmap.h>
>  #include <linux/platform_device.h>
>  #include <linux/i2c.h>
> +#include <linux/gpio.h>
>  #include <mach/hardware.h>
>  #include <linux/io.h>
>  #include <linux/irq.h>
> @@ -176,11 +177,35 @@ static struct platform_device em7210_serial_device = {
>  	.resource	= &em7210_uart_resource,
>  };
>  
> +#define EM7210_HARDWARE_POWER 0
> +
>  void em7210_power_off(void)
>  {
> -	*IOP3XX_GPOE &= 0xfe;
> -	*IOP3XX_GPOD |= 0x01;
> +	int ret;
> +
> +	ret = gpio_direction_output(EM7210_HARDWARE_POWER, 1);

btw, any reason for not using gpio_direction_output() in
em7210_request_gpios() and gpio_set_value() here ? (just wondering)

I can't test it on my ss4000e but at least this patch looks fine.

Arnaud

[PATCH v2] ARM: iop32x: fix power off handling for the EM7210 board

[Linus Walleij]

On Thu, Jan 30, 2014 at 12:19 AM, Arnaud Patard
<arnaud.patard@rtp-net.org> wrote:
> Linus Walleij <linus.walleij@linaro.org> writes:

>>  void em7210_power_off(void)
>>  {
>> -     *IOP3XX_GPOE &= 0xfe;
>> -     *IOP3XX_GPOD |= 0x01;
>> +     int ret;
>> +
>> +     ret = gpio_direction_output(EM7210_HARDWARE_POWER, 1);
>
> btw, any reason for not using gpio_direction_output() in
> em7210_request_gpios() and gpio_set_value() here ? (just wondering)

Mainly because the old code did not drive a default value on
the pin (which would be zero then) but relies on the power-on
default.

So by not doing this I'm not poking any hardware that wasn't poked
earlier.

> I can't test it on my ss4000e but at least this patch looks fine.

Would be nice!

Yours,
Linus Walleij

[PATCH v2] ARM: iop32x: fix power off handling for the EM7210 board

[Kevin Hilman]

Linus Walleij <linus.walleij@linaro.org> writes:

> This board was missed when converting all the others to proper
> abstracted GPIO handling. Fix it up the right way by requesting
> and driving GPIO line 0 high through gpiolib to power off the
> machine.
>
> Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
> Reported-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Queueing for fixes (w/ack from Arnd.)

Kevin