[PATCH v4 1/1] mmc: dw_mmc: Add runtime pm to dw_mmc

From: Karol Wrona
Date: Thu Mar 19 2015 - 09:44:49 EST


This patch adds runtime pm handling to dw_mmc.
It mainly uses mci_request/mci_request_end for mmc host state information.
The goal of the runtime pm in dw_mmc host is mainly for giving an information
for containing it power domain about its activity.

Signed-off-by: Karol Wrona <k.wrona@xxxxxxxxxxx>
Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
---
drivers/mmc/host/dw_mmc.c | 117 +++++++++++++++++++++++++++++++++++++++++----
drivers/mmc/host/dw_mmc.h | 2 +
2 files changed, 110 insertions(+), 9 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 47dfd0e..086cabc 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -38,6 +38,7 @@
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/mmc/slot-gpio.h>
+#include <linux/pm_runtime.h>

#include "dw_mmc.h"

@@ -104,6 +105,29 @@ static bool dw_mci_reset(struct dw_mci *host);
static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset);
static int dw_mci_card_busy(struct mmc_host *mmc);

+#ifdef CONFIG_PM
+static inline int dw_mci_pm_runtime_get(struct dw_mci *host)
+{
+ return pm_runtime_get_sync(host->dev);
+}
+
+static inline int dw_mci_pm_runtime_put(struct dw_mci *host)
+{
+ pm_runtime_mark_last_busy(host->dev);
+ return pm_runtime_put_autosuspend(host->dev);
+}
+#else /* !CONFIG_PM */
+static inline int dw_mci_pm_runtime_get(struct dw_mci *host)
+{
+ return 0;
+}
+
+static inline int dw_mci_pm_runtime_put(struct dw_mci *host)
+{
+ return 0;
+}
+#endif /* CONFIG_PM */
+
#if defined(CONFIG_DEBUG_FS)
static int dw_mci_req_show(struct seq_file *s, void *v)
{
@@ -113,6 +137,8 @@ static int dw_mci_req_show(struct seq_file *s, void *v)
struct mmc_command *stop;
struct mmc_data *data;

+ dw_mci_pm_runtime_get(slot->host);
+
/* Make sure we get a consistent snapshot */
spin_lock_bh(&slot->host->lock);
mrq = slot->mrq;
@@ -142,6 +168,8 @@ static int dw_mci_req_show(struct seq_file *s, void *v)

spin_unlock_bh(&slot->host->lock);

+ dw_mci_pm_runtime_put(slot->host);
+
return 0;
}

@@ -1071,6 +1099,8 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)

WARN_ON(slot->mrq);

+ dw_mci_pm_runtime_get(host);
+
/*
* The check for card presence and queueing of the request must be
* atomic, otherwise the card could be removed in between and the
@@ -1082,6 +1112,8 @@ static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
spin_unlock_bh(&host->lock);
mrq->cmd->error = -ENOMEDIUM;
mmc_request_done(mmc, mrq);
+
+ dw_mci_pm_runtime_put(host);
return;
}

@@ -1109,6 +1141,8 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
slot->ctype = SDMMC_CTYPE_1BIT;
}

+ dw_mci_pm_runtime_get(slot->host);
+
regs = mci_readl(slot->host, UHS_REG);

/* DDR mode set */
@@ -1139,7 +1173,7 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
dev_err(slot->host->dev,
"failed to enable vmmc regulator\n");
/*return, if failed turn on vmmc*/
- return;
+ goto out;
}
}
set_bit(DW_MMC_CARD_NEED_INIT, &slot->flags);
@@ -1192,6 +1226,9 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)

if (slot->host->state == STATE_WAITING_CMD11_DONE && ios->clock != 0)
slot->host->state = STATE_IDLE;
+
+out:
+ dw_mci_pm_runtime_put(slot->host);
}

static int dw_mci_card_busy(struct mmc_host *mmc)
@@ -1199,12 +1236,16 @@ static int dw_mci_card_busy(struct mmc_host *mmc)
struct dw_mci_slot *slot = mmc_priv(mmc);
u32 status;

+ dw_mci_pm_runtime_get(slot->host);
+
/*
* Check the busy bit which is low when DAT[3:0]
* (the data lines) are 0000
*/
status = mci_readl(slot->host, STATUS);

+ dw_mci_pm_runtime_put(slot->host);
+
return !!(status & SDMMC_STATUS_BUSY);
}

@@ -1215,7 +1256,9 @@ static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios)
u32 uhs;
u32 v18 = SDMMC_UHS_18V << slot->id;
int min_uv, max_uv;
- int ret;
+ int ret = 0;
+
+ dw_mci_pm_runtime_get(host);

/*
* Program the voltage. Note that some instances of dw_mmc may use
@@ -1239,12 +1282,16 @@ static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios)
dev_dbg(&mmc->class_dev,
"Regulator set error %d: %d - %d\n",
ret, min_uv, max_uv);
- return ret;
+
+ goto out;
}
}
mci_writel(host, UHS_REG, uhs);

- return 0;
+out:
+ dw_mci_pm_runtime_put(host);
+
+ return ret;
}

static int dw_mci_get_ro(struct mmc_host *mmc)
@@ -1253,6 +1300,8 @@ static int dw_mci_get_ro(struct mmc_host *mmc)
struct dw_mci_slot *slot = mmc_priv(mmc);
int gpio_ro = mmc_gpio_get_ro(mmc);

+ dw_mci_pm_runtime_get(slot->host);
+
/* Use platform get_ro function, else try on board write protect */
if ((slot->quirks & DW_MCI_SLOT_QUIRK_NO_WRITE_PROTECT) ||
(slot->host->quirks & DW_MCI_QUIRK_NO_WRITE_PROTECT))
@@ -1263,6 +1312,8 @@ static int dw_mci_get_ro(struct mmc_host *mmc)
read_only =
mci_readl(slot->host, WRTPRT) & (1 << slot->id) ? 1 : 0;

+ dw_mci_pm_runtime_put(slot->host);
+
dev_dbg(&mmc->class_dev, "card is %s\n",
read_only ? "read-only" : "read-write");

@@ -1277,6 +1328,8 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
struct dw_mci *host = slot->host;
int gpio_cd = mmc_gpio_get_cd(mmc);

+ dw_mci_pm_runtime_get(host);
+
/* Use platform get_cd function, else try onboard card detect */
if (brd->quirks & DW_MCI_QUIRK_BROKEN_CARD_DETECTION)
present = 1;
@@ -1296,6 +1349,8 @@ static int dw_mci_get_cd(struct mmc_host *mmc)
}
spin_unlock_bh(&host->lock);

+ dw_mci_pm_runtime_put(host);
+
return present;
}

@@ -1304,6 +1359,8 @@ static void dw_mci_init_card(struct mmc_host *mmc, struct mmc_card *card)
struct dw_mci_slot *slot = mmc_priv(mmc);
struct dw_mci *host = slot->host;

+ dw_mci_pm_runtime_get(host);
+
/*
* Low power mode will stop the card clock when idle. According to the
* description of the CLKENA register we should disable low power mode
@@ -1331,6 +1388,8 @@ static void dw_mci_init_card(struct mmc_host *mmc, struct mmc_card *card)
SDMMC_CMD_PRV_DAT_WAIT, 0);
}
}
+
+ dw_mci_pm_runtime_put(host);
}

static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)
@@ -1340,6 +1399,9 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)
unsigned long irqflags;
u32 int_mask;

+ if (enb)
+ dw_mci_pm_runtime_get(slot->host);
+
spin_lock_irqsave(&host->irq_lock, irqflags);

/* Enable/disable Slot Specific SDIO interrupt */
@@ -1351,6 +1413,10 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)
mci_writel(host, INTMASK, int_mask);

spin_unlock_irqrestore(&host->irq_lock, irqflags);
+
+ /* If interrupt is enabled leave device active. */
+ if (!enb)
+ dw_mci_pm_runtime_put(slot->host);
}

static int dw_mci_execute_tuning(struct mmc_host *mmc, u32 opcode)
@@ -1360,8 +1426,13 @@ static int dw_mci_execute_tuning(struct mmc_host *mmc, u32 opcode)
const struct dw_mci_drv_data *drv_data = host->drv_data;
int err = -ENOSYS;

+ dw_mci_pm_runtime_get(host);
+
if (drv_data && drv_data->execute_tuning)
err = drv_data->execute_tuning(slot);
+
+ dw_mci_pm_runtime_put(host);
+
return err;
}

@@ -1371,9 +1442,13 @@ static int dw_mci_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios
struct dw_mci *host = slot->host;
const struct dw_mci_drv_data *drv_data = host->drv_data;

+ dw_mci_pm_runtime_get(host);
+
if (drv_data && drv_data->prepare_hs400_tuning)
return drv_data->prepare_hs400_tuning(host, ios);

+ dw_mci_pm_runtime_put(host);
+
return 0;
}

@@ -1414,10 +1489,13 @@ static void dw_mci_request_end(struct dw_mci *host, struct mmc_request *mrq)
} else {
dev_vdbg(host->dev, "list empty\n");

- if (host->state == STATE_SENDING_CMD11)
+ if (host->state == STATE_SENDING_CMD11) {
host->state = STATE_WAITING_CMD11_DONE;
- else
+ } else {
+ dw_mci_pm_runtime_put(host);
+
host->state = STATE_IDLE;
+ }
}

spin_unlock(&host->lock);
@@ -2688,6 +2766,11 @@ int dw_mci_probe(struct dw_mci *host)
return -ENODEV;
}

+ pm_runtime_enable(host->dev);
+ pm_runtime_get_sync(host->dev);
+ pm_runtime_set_autosuspend_delay(host->dev, DWMMC_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(host->dev);
+
host->biu_clk = devm_clk_get(host->dev, "biu");
if (IS_ERR(host->biu_clk)) {
dev_dbg(host->dev, "biu clock not available\n");
@@ -2877,6 +2960,10 @@ int dw_mci_probe(struct dw_mci *host)
if (host->quirks & DW_MCI_QUIRK_IDMAC_DTO)
dev_info(host->dev, "Internal DMAC interrupt fix enabled.\n");

+ /* no pm runtime wrappers in probe just to be consistent */
+ pm_runtime_mark_last_busy(host->dev);
+ pm_runtime_put_autosuspend(host->dev);
+
return 0;

err_dmaunmap:
@@ -2891,6 +2978,9 @@ err_clk_biu:
if (!IS_ERR(host->biu_clk))
clk_disable_unprepare(host->biu_clk);

+ pm_runtime_put_sync(host->dev);
+ pm_runtime_disable(host->dev);
+
return ret;
}
EXPORT_SYMBOL(dw_mci_probe);
@@ -2899,6 +2989,8 @@ void dw_mci_remove(struct dw_mci *host)
{
int i;

+ pm_runtime_get_sync(host->dev);
+
mci_writel(host, RINTSTS, 0xFFFFFFFF);
mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */

@@ -2915,6 +3007,9 @@ void dw_mci_remove(struct dw_mci *host)
if (host->use_dma && host->dma_ops->exit)
host->dma_ops->exit(host);

+ pm_runtime_put_sync(host->dev);
+ pm_runtime_disable(host->dev);
+
if (!IS_ERR(host->ciu_clk))
clk_disable_unprepare(host->ciu_clk);

@@ -2937,11 +3032,13 @@ EXPORT_SYMBOL(dw_mci_suspend);

int dw_mci_resume(struct dw_mci *host)
{
- int i, ret;
+ int i;
+
+ dw_mci_pm_runtime_get(host);

if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_ALL_RESET_FLAGS)) {
- ret = -ENODEV;
- return ret;
+ dw_mci_pm_runtime_put(host);
+ return -ENODEV;
}

if (host->use_dma && host->dma_ops->init)
@@ -2976,6 +3073,8 @@ int dw_mci_resume(struct dw_mci *host)
/* Now that slots are all setup, we can enable card detect */
dw_mci_enable_cd(host);

+ dw_mci_pm_runtime_put(host);
+
return 0;
}
EXPORT_SYMBOL(dw_mci_resume);
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index d239867..2317f4b7 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -209,6 +209,8 @@ extern int dw_mci_suspend(struct dw_mci *host);
extern int dw_mci_resume(struct dw_mci *host);
#endif

+#define DWMMC_AUTOSUSPEND_DELAY 50
+
/**
* struct dw_mci_slot - MMC slot state
* @mmc: The mmc_host representing this slot.
--
1.7.9.5

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