[PATCH] pinctrl-baytrail, mmc/sdhci-acpi: Fix for Intel Baytrail-T mmc_pwr pin
From: Jon Pry
Date: Sun May 11 2014 - 17:36:26 EST
Most of this patch was probably written by Doug Johnson. He never
submitted it and I have removed spurious dependencies on moving
certain gpio chips to ACPI control.
----
Baytrail_T has errata regarding a non-functioning mmc_pwr pin. This
patch reconfigures
said pin as a GPIO and adds SDHCI quirks to support such functionality
Signed-off-by: Jon Pry <jonpry <at> gmail.com>
---
drivers/mmc/host/sdhci-acpi.c | 2 +-
drivers/mmc/host/sdhci.c | 30 ++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci.h | 11 ++++++-----
drivers/pinctrl/pinctrl-baytrail.c | 9 ++++++---
include/linux/mmc/sdhci.h | 3 +++
5 files changed, 46 insertions(+), 9 deletions(-)
diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c
index ebb3f39..ebed2a0 100644
--- a/drivers/mmc/host/sdhci-acpi.c
+++ b/drivers/mmc/host/sdhci-acpi.c
@@ -123,7 +123,7 @@ static const struct sdhci_acpi_slot
sdhci_acpi_slot_int_emmc = {
static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sdio = {
.quirks = SDHCI_QUIRK_BROKEN_CARD_DETECTION,
- .quirks2 = SDHCI_QUIRK2_HOST_OFF_CARD_ON,
+ .quirks2 = SDHCI_QUIRK2_HOST_OFF_CARD_ON |
SDHCI_QUIRK2_BROKEN_POWER_ENABLE,
.caps = MMC_CAP_NONREMOVABLE | MMC_CAP_POWER_OFF_CARD,
.flags = SDHCI_ACPI_RUNTIME_PM,
.pm_caps = MMC_PM_KEEP_POWER,
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9a79fc4..7a06008 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -22,6 +22,7 @@
#include <linux/scatterlist.h>
#include <linux/regulator/consumer.h>
#include <linux/pm_runtime.h>
+#include <linux/gpio.h>
#include <linux/leds.h>
@@ -1261,6 +1262,10 @@ static inline void sdhci_update_clock(struct
sdhci_host *host)
sdhci_set_clock(host, clock);
}
+static inline void sdhci_set_power_quirk(unsigned short power) {
+ gpio_set_value(SDHCI_POWER_QUIRK_GPIO, power);
+}
+
static int sdhci_set_power(struct sdhci_host *host, unsigned short power)
{
u8 pwr = 0;
@@ -1292,6 +1297,9 @@ static int sdhci_set_power(struct sdhci_host
*host, unsigned short power)
sdhci_writeb(host, 0, SDHCI_POWER_CONTROL);
if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
sdhci_runtime_pm_bus_off(host);
+ /* The intel Bay Trail SoCs need to assert a GPIO as a work around */
+ if (host->quirks2 & SDHCI_QUIRK2_BROKEN_POWER_ENABLE)
+ sdhci_set_power_quirk(0);
return 0;
}
@@ -1311,8 +1319,14 @@ static int sdhci_set_power(struct sdhci_host
*host, unsigned short power)
pwr |= SDHCI_POWER_ON;
+
sdhci_writeb(host, pwr, SDHCI_POWER_CONTROL);
+ /* The intel Bay Trail SoCs need to assert a GPIO as a work around */
+ if (host->quirks2 & SDHCI_QUIRK2_BROKEN_POWER_ENABLE)
+ sdhci_set_power_quirk(1);
+
+
if (host->quirks2 & SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON)
sdhci_runtime_pm_bus_on(host);
@@ -2820,6 +2834,18 @@ int sdhci_add_host(struct sdhci_host *host)
host->flags &= ~SDHCI_USE_SDMA;
}
+ if ((host->quirks2 & SDHCI_QUIRK2_BROKEN_POWER_ENABLE)) {
+ printk("Using GPIO for power enable as it is marked broken\n");
+ if (gpio_request(SDHCI_POWER_QUIRK_GPIO, "SDIO_PWR_EN") < 0) {
+ printk("Unable to request GPIO. SDIO may be broken.");
+ host->quirks2 = host->quirks2 & ~SDHCI_QUIRK2_BROKEN_POWER_ENABLE;
+ }
+ else if (gpio_direction_output(SDHCI_POWER_QUIRK_GPIO, 0) < 0) {
+ printk("Unable to set GPIO direction. SDIO may be broken.");
+ host->quirks2 = host->quirks2 & ~SDHCI_QUIRK2_BROKEN_POWER_ENABLE;
+ }
+ }
+
if ((host->version >= SDHCI_SPEC_200) &&
(caps[0] & SDHCI_CAN_DO_ADMA2))
host->flags |= SDHCI_USE_ADMA;
@@ -3325,6 +3351,10 @@ void sdhci_remove_host(struct sdhci_host *host, int dead)
tasklet_kill(&host->card_tasklet);
tasklet_kill(&host->finish_tasklet);
+ if (host->quirks2 & SDHCI_QUIRK2_BROKEN_POWER_ENABLE) {
+ gpio_free(SDHCI_POWER_QUIRK_GPIO);
+ }
+
if (host->vmmc) {
regulator_disable(host->vmmc);
regulator_put(host->vmmc);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 0a3ed01..027fcd1 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -84,11 +84,12 @@
#define SDHCI_CTRL_ADMA64 0x18
#define SDHCI_CTRL_8BITBUS 0x20
-#define SDHCI_POWER_CONTROL 0x29
-#define SDHCI_POWER_ON 0x01
-#define SDHCI_POWER_180 0x0A
-#define SDHCI_POWER_300 0x0C
-#define SDHCI_POWER_330 0x0E
+#define SDHCI_POWER_CONTROL 0x29
+#define SDHCI_POWER_ON 0x01
+#define SDHCI_POWER_180 0x0A
+#define SDHCI_POWER_300 0x0C
+#define SDHCI_POWER_330 0x0E
+#define SDHCI_POWER_QUIRK_GPIO 195 /*GPIO offset 41 of SCORE device
is SD3_PWR_EN*/
#define SDHCI_BLOCK_GAP_CONTROL 0x2A
diff --git a/drivers/pinctrl/pinctrl-baytrail.c
b/drivers/pinctrl/pinctrl-baytrail.c
index 6e8301f..78060f0 100644
--- a/drivers/pinctrl/pinctrl-baytrail.c
+++ b/drivers/pinctrl/pinctrl-baytrail.c
@@ -151,9 +151,9 @@ static void __iomem *byt_gpio_reg(struct gpio_chip
*chip, unsigned offset,
static bool is_special_pin(struct byt_gpio *vg, unsigned offset)
{
- /* SCORE pin 92-93 */
+ /* SCORE pin 92-93; 41 for SDIO pwr_en bug */
if (!strcmp(vg->range->name, BYT_SCORE_ACPI_UID) &&
- offset >= 92 && offset <= 93)
+ ((offset >= 92 && offset <= 93) || (offset == 41)))
return true;
/* SUS pin 11-21 */
@@ -176,6 +176,10 @@ static int byt_gpio_request(struct gpio_chip
*chip, unsigned offset)
* But, some pins may have func pin mux 001 represents
* GPIO function. Only allow user to export pin with
* func pin mux preset as GPIO function by BIOS/FW.
+ *
+ * We do make an exception, however, for pin 41 which
+ * is needed in order to power up the SDIO bus (as per
+ * the intel erratum)
*/
value = readl(reg) & BYT_PIN_MUX;
special = is_special_pin(vg, offset);
@@ -184,7 +188,6 @@ static int byt_gpio_request(struct gpio_chip
*chip, unsigned offset)
"pin %u cannot be used as GPIO.\n", offset);
return -EINVAL;
}
-
pm_runtime_get(&vg->pdev->dev);
return 0;
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 7be12b8..92cec16 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -102,6 +102,9 @@ struct sdhci_host {
#define SDHCI_QUIRK2_BROKEN_HS200 (1<<6)
/* Controller does not support DDR50 */
#define SDHCI_QUIRK2_BROKEN_DDR50 (1<<7)
+/* Controller cannot initialize power (must use GPIO instead) */
+#define SDHCI_QUIRK2_BROKEN_POWER_ENABLE (1<<8)
+
int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.7.10.4
--
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