Subject: [PATCH 1/2] OMAP2+: UART: Fix incorrect population of default uart pads

From: [email-masked] (Kevin Hilman)
Date: Mon, 23 Apr 2012 16:45:57 -0700

"Govindraj.R" <[email-masked]> writes:

> From: "Govindraj.R" <[email-masked]>
>
> The following commit:
> (7496ba3  ARM: OMAP2+: UART: Add default mux for all uarts)
> added default pads for all uarts. But not all boards tend to
> use all uarts and most of unused uart pins are muxed for
> other purpose. This commit breaks the modules which where trying
> to use unused uart pins on their boards.
>
> So remove the default pads adding.

I just noticed that this patch breaks runtime PM & wakeups for UART
console (at least on 3530/Overo with ttyO2 console.)

By removing the pads, the initial device_init_wakeup() is not called on
port init.  Without this call serial_omap_pm() disables runtime PM
because it checks device_may_wakeup().

Since runtime PM was disabled, I manually re-enabled it and then enabled
wakeups: 

  echo auto > /sys/devices/platform/omap_uart.2/power/control
  echo enabled > /sys/devices/platform/omap_uart.2/tty/ttyO2/power/wakeup

Then, after enabling auto-suspend timeouts, it seems wakeups are still
not working since the console hangs.

Reverting $SUBJECT patch gets things working again.

Kevin

> Cc: Felipe Balbi <[email-masked]>
> Cc: Kevin Hilman <[email-masked]>
> Cc: Russ Dill <[email-masked]>
> Reported-by: Tony Lindgren <[email-masked]>
> Signed-off-by: Govindraj.R <[email-masked]>
> ---
>  arch/arm/mach-omap2/serial.c |  116 ------------------------------------------
>  1 files changed, 0 insertions(+), 116 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
> index c9503a7..1554233 100644
> --- a/arch/arm/mach-omap2/serial.c
> +++ b/arch/arm/mach-omap2/serial.c
> @@ -120,124 +120,8 @@ static void omap_uart_set_smartidle(struct platform_device *pdev) {}
>  #endif /* CONFIG_PM */
>  
>  #ifdef CONFIG_OMAP_MUX
> -static struct omap_device_pad default_uart1_pads[] __initdata = {
> -	{
> -		.name	= "uart1_cts.uart1_cts",
> -		.enable	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart1_rts.uart1_rts",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart1_tx.uart1_tx",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart1_rx.uart1_rx",
> -		.flags	= OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
> -		.enable	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -		.idle	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -	},
> -};
> -
> -static struct omap_device_pad default_uart2_pads[] __initdata = {
> -	{
> -		.name	= "uart2_cts.uart2_cts",
> -		.enable	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart2_rts.uart2_rts",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart2_tx.uart2_tx",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart2_rx.uart2_rx",
> -		.flags	= OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
> -		.enable	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -		.idle	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -	},
> -};
> -
> -static struct omap_device_pad default_uart3_pads[] __initdata = {
> -	{
> -		.name	= "uart3_cts_rctx.uart3_cts_rctx",
> -		.enable	= OMAP_PIN_INPUT_PULLUP | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart3_rts_sd.uart3_rts_sd",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart3_tx_irtx.uart3_tx_irtx",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart3_rx_irrx.uart3_rx_irrx",
> -		.flags	= OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
> -		.enable	= OMAP_PIN_INPUT | OMAP_MUX_MODE0,
> -		.idle	= OMAP_PIN_INPUT | OMAP_MUX_MODE0,
> -	},
> -};
> -
> -static struct omap_device_pad default_omap36xx_uart4_pads[] __initdata = {
> -	{
> -		.name   = "gpmc_wait2.uart4_tx",
> -		.enable = OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "gpmc_wait3.uart4_rx",
> -		.flags	= OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
> -		.enable	= OMAP_PIN_INPUT | OMAP_MUX_MODE2,
> -		.idle	= OMAP_PIN_INPUT | OMAP_MUX_MODE2,
> -	},
> -};
> -
> -static struct omap_device_pad default_omap4_uart4_pads[] __initdata = {
> -	{
> -		.name	= "uart4_tx.uart4_tx",
> -		.enable	= OMAP_PIN_OUTPUT | OMAP_MUX_MODE0,
> -	},
> -	{
> -		.name	= "uart4_rx.uart4_rx",
> -		.flags	= OMAP_DEVICE_PAD_REMUX | OMAP_DEVICE_PAD_WAKEUP,
> -		.enable	= OMAP_PIN_INPUT | OMAP_MUX_MODE0,
> -		.idle	= OMAP_PIN_INPUT | OMAP_MUX_MODE0,
> -	},
> -};
> -
>  static void omap_serial_fill_default_pads(struct omap_board_data *bdata)
>  {
> -	switch (bdata->id) {
> -	case 0:
> -		bdata->pads = default_uart1_pads;
> -		bdata->pads_cnt = ARRAY_SIZE(default_uart1_pads);
> -		break;
> -	case 1:
> -		bdata->pads = default_uart2_pads;
> -		bdata->pads_cnt = ARRAY_SIZE(default_uart2_pads);
> -		break;
> -	case 2:
> -		bdata->pads = default_uart3_pads;
> -		bdata->pads_cnt = ARRAY_SIZE(default_uart3_pads);
> -		break;
> -	case 3:
> -		if (cpu_is_omap44xx()) {
> -			bdata->pads = default_omap4_uart4_pads;
> -			bdata->pads_cnt =
> -				ARRAY_SIZE(default_omap4_uart4_pads);
> -		} else if (cpu_is_omap3630()) {
> -			bdata->pads = default_omap36xx_uart4_pads;
> -			bdata->pads_cnt =
> -				ARRAY_SIZE(default_omap36xx_uart4_pads);
> -		}
> -		break;
> -	default:
> -		break;
> -	}
>  }
>  #else
>  static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {}