[PATCH v2] mmc: atmel-mci: add runtime pm support
Wenyou Yang
wenyou.yang at atmel.com
Wed Oct 29 21:00:41 PDT 2014
Add runtime pm support to atmel mci controller.
Use runtime pm APIs to enable/disable atmel mci's clock.
Use runtime autosuspend APIs to enable auto suspend delay.
Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
---
Changes v1 -> v2:
* Adjust the APIs and invoking sequence to avoid clock unbalance issue during ->probe.
* Fix miss to invoke clk_disable_unprepare() in the error handling in ->probe.
* Remove atmci_suspend/resume and use pm_runtime_force_suspend/resume() to simplify code.
drivers/mmc/host/atmel-mci.c | 90 +++++++++++++++++++++++++++++++-----------
1 file changed, 67 insertions(+), 23 deletions(-)
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 0b9ddf8..f8f2bbe 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -37,6 +37,8 @@
#include <linux/atmel-mci.h>
#include <linux/atmel_pdc.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
#include <asm/cacheflush.h>
#include <asm/io.h>
@@ -44,6 +46,8 @@
#include "atmel-mci-regs.h"
+#define AUTOSUSPEND_DELAY 50
+
#define ATMCI_DATA_ERROR_FLAGS (ATMCI_DCRCE | ATMCI_DTOE | ATMCI_OVRE | ATMCI_UNRE)
#define ATMCI_DMA_THRESHOLD 16
@@ -386,20 +390,19 @@ static int atmci_regs_show(struct seq_file *s, void *v)
if (!buf)
return -ENOMEM;
+ pm_runtime_get_sync(&host->pdev->dev);
+
/*
* Grab a more or less consistent snapshot. Note that we're
* not disabling interrupts, so IMR and SR may not be
* consistent.
*/
- ret = clk_prepare_enable(host->mck);
- if (ret)
- goto out;
-
spin_lock_bh(&host->lock);
memcpy_fromio(buf, host->regs, ATMCI_REGS_SIZE);
spin_unlock_bh(&host->lock);
- clk_disable_unprepare(host->mck);
+ pm_runtime_mark_last_busy(&host->pdev->dev);
+ pm_runtime_put_autosuspend(&host->pdev->dev);
seq_printf(s, "MR:\t0x%08x%s%s ",
buf[ATMCI_MR / 4],
@@ -449,7 +452,6 @@ static int atmci_regs_show(struct seq_file *s, void *v)
val & ATMCI_CFG_LSYNC ? " LSYNC" : "");
}
-out:
kfree(buf);
return ret;
@@ -1252,6 +1254,8 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
WARN_ON(slot->mrq);
dev_dbg(&host->pdev->dev, "MRQ: cmd %u\n", mrq->cmd->opcode);
+ pm_runtime_get_sync(&host->pdev->dev);
+
/*
* We may "know" the card is gone even though there's still an
* electrical connection. If so, we really need to communicate
@@ -1281,7 +1285,8 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
struct atmel_mci_slot *slot = mmc_priv(mmc);
struct atmel_mci *host = slot->host;
unsigned int i;
- bool unprepare_clk;
+
+ pm_runtime_get_sync(&host->pdev->dev);
slot->sdc_reg &= ~ATMCI_SDCBUS_MASK;
switch (ios->bus_width) {
@@ -1297,13 +1302,8 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
unsigned int clock_min = ~0U;
u32 clkdiv;
- clk_prepare(host->mck);
- unprepare_clk = true;
-
spin_lock_bh(&host->lock);
if (!host->mode_reg) {
- clk_enable(host->mck);
- unprepare_clk = false;
atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
if (host->caps.has_cfg_reg)
@@ -1371,8 +1371,6 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
} else {
bool any_slot_active = false;
- unprepare_clk = false;
-
spin_lock_bh(&host->lock);
slot->clock = 0;
for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
@@ -1385,17 +1383,12 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
if (host->mode_reg) {
atmci_readl(host, ATMCI_MR);
- clk_disable(host->mck);
- unprepare_clk = true;
}
host->mode_reg = 0;
}
spin_unlock_bh(&host->lock);
}
- if (unprepare_clk)
- clk_unprepare(host->mck);
-
switch (ios->power_mode) {
case MMC_POWER_OFF:
if (!IS_ERR(mmc->supply.vmmc))
@@ -1421,6 +1414,9 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
*/
break;
}
+
+ pm_runtime_mark_last_busy(&host->pdev->dev);
+ pm_runtime_put_autosuspend(&host->pdev->dev);
}
static int atmci_get_ro(struct mmc_host *mmc)
@@ -1512,6 +1508,9 @@ static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
spin_unlock(&host->lock);
mmc_request_done(prev_mmc, mrq);
spin_lock(&host->lock);
+
+ pm_runtime_mark_last_busy(&host->pdev->dev);
+ pm_runtime_put_autosuspend(&host->pdev->dev);
}
static void atmci_command_complete(struct atmel_mci *host,
@@ -2417,15 +2416,16 @@ static int __init atmci_probe(struct platform_device *pdev)
atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
host->bus_hz = clk_get_rate(host->mck);
- clk_disable_unprepare(host->mck);
host->mapbase = regs->start;
tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)host);
ret = request_irq(irq, atmci_interrupt, 0, dev_name(&pdev->dev), host);
- if (ret)
+ if (ret) {
+ clk_disable_unprepare(host->mck);
return ret;
+ }
/* Get MCI capabilities and set operations according to it */
atmci_get_cap(host);
@@ -2449,6 +2449,12 @@ static int __init atmci_probe(struct platform_device *pdev)
setup_timer(&host->timer, atmci_timeout_timer, (unsigned long)host);
+ pm_runtime_get_noresume(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
/* We need at least one slot to succeed */
nr_slots = 0;
ret = -ENODEV;
@@ -2491,6 +2497,9 @@ static int __init atmci_probe(struct platform_device *pdev)
"Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
host->mapbase, irq, nr_slots);
+ pm_runtime_mark_last_busy(&host->pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);
+
return 0;
err_dma_alloc:
@@ -2499,6 +2508,11 @@ err_dma_alloc:
atmci_cleanup_slot(host->slot[i], i);
}
err_init_slot:
+ clk_disable_unprepare(host->mck);
+
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+
del_timer_sync(&host->timer);
if (host->dma.chan)
dma_release_channel(host->dma.chan);
@@ -2511,6 +2525,8 @@ static int __exit atmci_remove(struct platform_device *pdev)
struct atmel_mci *host = platform_get_drvdata(pdev);
unsigned int i;
+ pm_runtime_get_sync(&pdev->dev);
+
if (host->buffer)
dma_free_coherent(&pdev->dev, host->buf_size,
host->buffer, host->buf_phys_addr);
@@ -2520,11 +2536,9 @@ static int __exit atmci_remove(struct platform_device *pdev)
atmci_cleanup_slot(host->slot[i], i);
}
- clk_prepare_enable(host->mck);
atmci_writel(host, ATMCI_IDR, ~0UL);
atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIDIS);
atmci_readl(host, ATMCI_SR);
- clk_disable_unprepare(host->mck);
del_timer_sync(&host->timer);
if (host->dma.chan)
@@ -2532,14 +2546,44 @@ static int __exit atmci_remove(struct platform_device *pdev)
free_irq(platform_get_irq(pdev, 0), host);
+ clk_disable_unprepare(host->mck);
+
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int atmci_runtime_suspend(struct device *dev)
+{
+ struct atmel_mci *host = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(host->mck);
+
return 0;
}
+static int atmci_runtime_resume(struct device *dev)
+{
+ struct atmel_mci *host = dev_get_drvdata(dev);
+
+ return clk_prepare_enable(host->mck);
+}
+
+static const struct dev_pm_ops atmci_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_PM_RUNTIME_PM_OPS(atmci_runtime_suspend, atmci_runtime_resume, NULL)
+};
+#endif
+
static struct platform_driver atmci_driver = {
.remove = __exit_p(atmci_remove),
.driver = {
.name = "atmel_mci",
.of_match_table = of_match_ptr(atmci_dt_ids),
+ .pm = &atmci_dev_pm_ops,
},
};
--
1.7.9.5
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