[U-Boot] [PATCH 06/10] dm: imx: Use gpio_request() to request GPIOs

Igor Grinberg grinberg at compulab.co.il
Mon Sep 15 19:13:28 CEST 2014


Hi Simon,

On 09/15/14 15:57, Simon Glass wrote:
> GPIOs should be requested before use. Without this, driver model will not
> permit the GPIO to be used.

Right. That should have been done from the start... Sorry for that...
A question below though..

> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> 
>  arch/arm/imx-common/i2c-mxv7.c | 14 ++++++++++++++
>  board/compulab/cm_fx6/cm_fx6.c |  9 +++++++++
>  board/compulab/cm_fx6/common.c |  3 +++
>  3 files changed, 26 insertions(+)
> 
> diff --git a/arch/arm/imx-common/i2c-mxv7.c b/arch/arm/imx-common/i2c-mxv7.c
> index a580873..7cea024 100644
> --- a/arch/arm/imx-common/i2c-mxv7.c
> +++ b/arch/arm/imx-common/i2c-mxv7.c
> @@ -4,6 +4,7 @@
>   * SPDX-License-Identifier:	GPL-2.0+
>   */
>  #include <common.h>
> +#include <malloc.h>
>  #include <asm/arch/clock.h>
>  #include <asm/arch/imx-regs.h>
>  #include <asm/errno.h>
> @@ -72,8 +73,21 @@ static void * const i2c_bases[] = {
>  void setup_i2c(unsigned i2c_index, int speed, int slave_addr,
>  		struct i2c_pads_info *p)
>  {
> +	char *name;
> +
>  	if (i2c_index >= ARRAY_SIZE(i2c_bases))
>  		return;
> +
> +	name = malloc(9);
> +	assert(name);
> +	sprintf(name, "i2c_sda%d", i2c_index);
> +	gpio_request(p->sda.gp, name);
> +
> +	name = malloc(9);
> +	assert(name);
> +	sprintf(name, "i2c_scl%d", i2c_index);
> +	gpio_request(p->scl.gp, name);
> +
>  	/* Enable i2c clock */
>  	enable_i2c_clk(1, i2c_index);
>  	/* Make sure bus is idle */
> diff --git a/board/compulab/cm_fx6/cm_fx6.c b/board/compulab/cm_fx6/cm_fx6.c
> index fdb8ebf..80a123d 100644
> --- a/board/compulab/cm_fx6/cm_fx6.c
> +++ b/board/compulab/cm_fx6/cm_fx6.c
> @@ -71,8 +71,15 @@ static iomux_v3_cfg_t const sata_pads[] = {
>  
>  static void cm_fx6_setup_issd(void)
>  {
> +	int i;
> +
>  	SETUP_IOMUX_PADS(sata_pads);
> +
> +	for (i = 0; i < ARRAY_SIZE(cm_fx6_issd_gpios); i++)
> +		gpio_request(cm_fx6_issd_gpios[i], "sata");
> +
>  	/* Make sure this gpio has logical 0 value */
> +	gpio_request(CM_FX6_SATA_PWLOSS_INT, "sata_pwloss_int");
>  	gpio_direction_output(CM_FX6_SATA_PWLOSS_INT, 0);
>  	udelay(100);
>  
> @@ -167,6 +174,7 @@ static int cm_fx6_usb_hub_reset(void)
>  	}
>  
>  	SETUP_IOMUX_PAD(PAD_SD3_RST__GPIO7_IO08 | MUX_PAD_CTRL(NO_PAD_CTRL));
> +	gpio_request(CM_FX6_USB_HUB_RST, "usb_hub_rst");
>  	gpio_direction_output(CM_FX6_USB_HUB_RST, 0);
>  	udelay(10);
>  	gpio_direction_output(CM_FX6_USB_HUB_RST, 1);
> @@ -324,6 +332,7 @@ int board_eth_init(bd_t *bis)
>  
>  	SETUP_IOMUX_PADS(enet_pads);
>  	/* phy reset */
> +	gpio_request(CM_FX6_ENET_NRST, "enet_nrst");
>  	gpio_direction_output(CM_FX6_ENET_NRST, 0);
>  	udelay(500);
>  	gpio_set_value(CM_FX6_ENET_NRST, 1);
> diff --git a/board/compulab/cm_fx6/common.c b/board/compulab/cm_fx6/common.c
> index 1f39679..562313b 100644
> --- a/board/compulab/cm_fx6/common.c
> +++ b/board/compulab/cm_fx6/common.c
> @@ -79,6 +79,9 @@ void cm_fx6_set_ecspi_iomux(void)
>  
>  int board_spi_cs_gpio(unsigned bus, unsigned cs)
>  {
> +#ifndef CONFIG_SPL_BUILD
> +	gpio_request(CM_FX6_ECSPI_BUS0_CS0, "ecspi_bus0_cs0");
> +#endif
>  	return (bus == 0 && cs == 0) ? (CM_FX6_ECSPI_BUS0_CS0) : -1;
>  }
>  #endif
> 

In all the above gpio_request() calls, I think we should check for
the return value.
Because after patch 8 in the series it can fail if if someone
double requests the same gpio.

-- 
Regards,
Igor.


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