ARM: PXA2xx: MFP: fix bug with MFP_LPM_KEEP_OUTPUT

Pins that have MFP_LPM_KEEP_OUTPUT set and are configured for output
must retain the output state in low power mode.
Currently, the pin direction configuration is overrided with values
in gpdr_lpm[] array and do not obey the MFP_LPM_KEEP_OUTPUT setting.

Fix the above bug and add some documentation to clarify the
MFP_LPM_KEEP_OUTPUT setting purpose.

Reported-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Tested-by: Paul Parsons <lost.distance@yahoo.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
This commit is contained in:
Igor Grinberg 2012-04-12 15:43:28 +03:00 committed by Haojian Zhuang
parent 9f9d27e3f3
commit a13b878780
2 changed files with 18 additions and 3 deletions

View file

@ -17,6 +17,7 @@
*
* bit 23 - Input/Output (PXA2xx specific)
* bit 24 - Wakeup Enable(PXA2xx specific)
* bit 25 - Keep Output (PXA2xx specific)
*/
#define MFP_DIR_IN (0x0 << 23)
@ -25,6 +26,12 @@
#define MFP_DIR(x) (((x) >> 23) & 0x1)
#define MFP_LPM_CAN_WAKEUP (0x1 << 24)
/*
* MFP_LPM_KEEP_OUTPUT must be specified for pins that need to
* retain their last output level (low or high).
* Note: MFP_LPM_KEEP_OUTPUT has no effect on pins configured for input.
*/
#define MFP_LPM_KEEP_OUTPUT (0x1 << 25)
#define WAKEUP_ON_EDGE_RISE (MFP_LPM_CAN_WAKEUP | MFP_LPM_EDGE_RISE)

View file

@ -366,14 +366,22 @@ static int pxa2xx_mfp_suspend(void)
}
for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
saved_gafr[0][i] = GAFR_L(i);
saved_gafr[1][i] = GAFR_U(i);
saved_gpdr[i] = GPDR(i * 32);
saved_pgsr[i] = PGSR(i);
GPDR(i * 32) = gpdr_lpm[i];
}
/* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
for (i = 0; i < pxa_last_gpio; i++) {
if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
(saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
GPDR(i) |= GPIO_bit(i);
else
GPDR(i) &= ~GPIO_bit(i);
}
return 0;
}