Re: [PATCH 2/4] PM: Workaround for taking care of gpio clocks

[Tony Lindgren <tony@atomide.com>]

* Jouni Hogander <jouni.hogander@nokia.com> [080815 10:47]:
> In omap3 gpios 2-6 are in per domain. Functional clocks for these
> should be disabled. This patch is needed until gpio driver disables
> gpio clocks.
> 
> GPIO modules in PER domain are not able to act as a wake up source if
> PER domain is in retention. PER domain sleep transition before MPU is
> prevented by leaving icks active. PER domain still enters retention
> together with MPU. When this happens IOPAD wake up mechanism is used
> for gpios.

As we talked offline.. Should we pass the GPIO wake-up configuration
from board-*.c files? Or can we always automatically do this safely
on 34xx?

Tony


> Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
> ---
>  arch/arm/mach-omap2/pm34xx.c |   54 +++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 53 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
> index f30fa9e..7d5d461 100644
> --- a/arch/arm/mach-omap2/pm34xx.c
> +++ b/arch/arm/mach-omap2/pm34xx.c
> @@ -53,6 +53,36 @@ static void (*saved_idle)(void);
>  
>  static struct powerdomain *mpu_pwrdm;
>  
> +/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> + * handles fcks correctly */
> +#define NUM_OF_PERGPIOS 5
> +static struct clk *gpio_fcks[NUM_OF_PERGPIOS];
> +
> +/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> + * handles fcks correctly */
> +static void per_gpio_clk_enable(void)
> +{
> +	int i;
> +	for (i = 1; i < NUM_OF_PERGPIOS + 1; i++)
> +		clk_enable(gpio_fcks[i-1]);
> +}
> +
> +/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> + * handles fcks correctly */
> +static void per_gpio_clk_disable(void)
> +{
> +	int i;
> +	for (i = 1; i < NUM_OF_PERGPIOS + 1; i++)
> +		clk_disable(gpio_fcks[i-1]);
> +}
> +
> +/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> + * handles fcks correctly */
> +static void gpio_fclk_mask(u32 *fclk)
> +{
> +	*fclk &= ~(0x1f << 13);
> +}
> +
>  /* PRCM Interrupt Handler for wakeups */
>  static irqreturn_t prcm_interrupt_handler (int irq, void *dev_id)
>  {
> @@ -169,8 +199,18 @@ static void omap_sram_idle(void)
>  
>  	omap2_gpio_prepare_for_retention();
>  
> +	/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> +	 * handles fcks correctly */
> +	if (clocks_off_while_idle)
> +		per_gpio_clk_disable();
> +
>  	_omap_sram_idle(NULL, save_state);
>  
> +	/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> +	 * handles fcks correctly */
> +	if (clocks_off_while_idle)
> +		per_gpio_clk_enable();
> +
>  	omap2_gpio_resume_after_retention();
>  }
>  
> @@ -200,6 +240,10 @@ static int omap3_fclks_active(void)
>  				  CM_FCLKEN);
>  	fck_per = cm_read_mod_reg(OMAP3430_PER_MOD,
>  				  CM_FCLKEN);
> +
> +	if (clocks_off_while_idle)
> +		gpio_fclk_mask(&fck_per);
> +
>  	if (fck_core1 | fck_core3 | fck_sgx | fck_dss |
>  	    fck_cam | fck_per | fck_usbhost)
>  		return 1;
> @@ -418,7 +462,8 @@ static int __init pwrdms_setup(struct powerdomain *pwrdm)
>  int __init omap3_pm_init(void)
>  {
>  	struct power_state *pwrst;
> -	int ret;
> +	char clk_name[11];
> +	int ret, i;
>  
>  	printk(KERN_ERR "Power Management for TI OMAP3.\n");
>  
> @@ -454,6 +499,13 @@ int __init omap3_pm_init(void)
>  
>  	pm_idle = omap3_pm_idle;
>  
> +	/* XXX This is for gpio fclk hack. Will be removed as gpio driver
> +	 * handles fcks correctly */
> +	for (i = 1; i < NUM_OF_PERGPIOS + 1; i++) {
> +		sprintf(clk_name, "gpio%d_fck", i + 1);
> +		gpio_fcks[i-1] = clk_get(NULL, clk_name);
> +	}
> +
>  err1:
>  	return ret;
>  err2:
> -- 
> 1.5.5
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html