spi_qsd: Add runtime PM support to SPI QSD driver
Enable and disable the clocks and gpios to the SPI controller
using runtime PM. This serves the dual purpose of reducing power
Consumption a little and letting the core know when the device is idle.
If runtime_pm is not supported, then make sure the device becomes
active in first transaction after system-suspend, instead of
system-resume.
CRs-Fixed: 460988
Change-Id: I2360b6f48491cd0e8e5f1ce54805079daf92e36b
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>
diff --git a/drivers/spi/spi_qsd.c b/drivers/spi/spi_qsd.c
index 5347add..bbbb401 100644
--- a/drivers/spi/spi_qsd.c
+++ b/drivers/spi/spi_qsd.c
@@ -41,8 +41,12 @@
#include <linux/pm_qos.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
+#include <linux/pm_runtime.h>
#include "spi_qsd.h"
+static int msm_spi_pm_resume_runtime(struct device *device);
+static int msm_spi_pm_suspend_runtime(struct device *device);
+
static inline int msm_spi_configure_gsbi(struct msm_spi *dd,
struct platform_device *pdev)
{
@@ -666,6 +670,10 @@
u32 op, ret = IRQ_NONE;
struct msm_spi *dd = dev_id;
+ if (pm_runtime_suspended(dd->dev)) {
+ dev_warn(dd->dev, "QUP: pm runtime suspend, irq:%d\n", irq);
+ return ret;
+ }
if (readl_relaxed(dd->base + SPI_ERROR_FLAGS) ||
readl_relaxed(dd->base + QUP_ERROR_FLAGS)) {
struct spi_master *master = dev_get_drvdata(dd->dev);
@@ -1395,36 +1403,22 @@
container_of(work, struct msm_spi, work_data);
unsigned long flags;
u32 status_error = 0;
- int rc = 0;
+
+ pm_runtime_get_sync(dd->dev);
mutex_lock(&dd->core_lock);
- /* Don't allow power collapse until we release mutex */
- if (pm_qos_request_active(&qos_req_list))
- pm_qos_update_request(&qos_req_list,
- dd->pm_lat);
+ /*
+ * Counter-part of system-suspend when runtime-pm is not enabled.
+ * This way, resume can be left empty and device will be put in
+ * active mode only if client requests anything on the bus
+ */
+ if (!pm_runtime_enabled(dd->dev))
+ msm_spi_pm_resume_runtime(dd->dev);
+
if (dd->use_rlock)
remote_mutex_lock(&dd->r_lock);
- /* Configure the spi clk, miso, mosi and cs gpio */
- if (dd->pdata->gpio_config) {
- rc = dd->pdata->gpio_config();
- if (rc) {
- dev_err(dd->dev,
- "%s: error configuring GPIOs\n",
- __func__);
- status_error = 1;
- }
- }
-
- rc = msm_spi_request_gpios(dd);
- if (rc)
- status_error = 1;
-
- clk_prepare_enable(dd->clk);
- clk_prepare_enable(dd->pclk);
- msm_spi_enable_irqs(dd);
-
if (!msm_spi_is_valid_state(dd)) {
dev_err(dd->dev, "%s: SPI operational state not valid\n",
__func__);
@@ -1432,6 +1426,7 @@
}
spin_lock_irqsave(&dd->queue_lock, flags);
+ dd->transfer_pending = 1;
while (!list_empty(&dd->queue)) {
dd->cur_msg = list_entry(dd->queue.next,
struct spi_message, queue);
@@ -1448,24 +1443,14 @@
dd->transfer_pending = 0;
spin_unlock_irqrestore(&dd->queue_lock, flags);
- msm_spi_disable_irqs(dd);
- clk_disable_unprepare(dd->clk);
- clk_disable_unprepare(dd->pclk);
-
- /* Free the spi clk, miso, mosi, cs gpio */
- if (!rc && dd->pdata && dd->pdata->gpio_release)
- dd->pdata->gpio_release();
- if (!rc)
- msm_spi_free_gpios(dd);
-
if (dd->use_rlock)
remote_mutex_unlock(&dd->r_lock);
- if (pm_qos_request_active(&qos_req_list))
- pm_qos_update_request(&qos_req_list,
- PM_QOS_DEFAULT_VALUE);
-
mutex_unlock(&dd->core_lock);
+
+ pm_runtime_mark_last_busy(dd->dev);
+ pm_runtime_put_autosuspend(dd->dev);
+
/* If needed, this can be done after the current message is complete,
and work can be continued upon resume. No motivation for now. */
if (dd->suspended)
@@ -1479,8 +1464,6 @@
struct spi_transfer *tr;
dd = spi_master_get_devdata(spi->master);
- if (dd->suspended)
- return -EBUSY;
if (list_empty(&msg->transfers) || !msg->complete)
return -EINVAL;
@@ -1500,11 +1483,6 @@
}
spin_lock_irqsave(&dd->queue_lock, flags);
- if (dd->suspended) {
- spin_unlock_irqrestore(&dd->queue_lock, flags);
- return -EBUSY;
- }
- dd->transfer_pending = 1;
list_add_tail(&msg->queue, &dd->queue);
spin_unlock_irqrestore(&dd->queue_lock, flags);
queue_work(dd->workqueue, &dd->work_data);
@@ -1535,36 +1513,17 @@
dd = spi_master_get_devdata(spi->master);
+ pm_runtime_get_sync(dd->dev);
+
mutex_lock(&dd->core_lock);
- if (dd->suspended) {
- mutex_unlock(&dd->core_lock);
- return -EBUSY;
- }
+
+ /* Counter-part of system-suspend when runtime-pm is not enabled. */
+ if (!pm_runtime_enabled(dd->dev))
+ msm_spi_pm_resume_runtime(dd->dev);
if (dd->use_rlock)
remote_mutex_lock(&dd->r_lock);
- /* Configure the spi clk, miso, mosi, cs gpio */
- if (dd->pdata->gpio_config) {
- rc = dd->pdata->gpio_config();
- if (rc) {
- dev_err(&spi->dev,
- "%s: error configuring GPIOs\n",
- __func__);
- rc = -ENXIO;
- goto err_setup_gpio;
- }
- }
-
- rc = msm_spi_request_gpios(dd);
- if (rc) {
- rc = -ENXIO;
- goto err_setup_gpio;
- }
-
- clk_prepare_enable(dd->clk);
- clk_prepare_enable(dd->pclk);
-
spi_ioc = readl_relaxed(dd->base + SPI_IO_CONTROL);
mask = SPI_IO_C_CS_N_POLARITY_0 << spi->chip_select;
if (spi->mode & SPI_CS_HIGH)
@@ -1591,18 +1550,19 @@
/* Ensure previous write completed before disabling the clocks */
mb();
- clk_disable_unprepare(dd->clk);
- clk_disable_unprepare(dd->pclk);
- /* Free the spi clk, miso, mosi, cs gpio */
- if (dd->pdata && dd->pdata->gpio_release)
- dd->pdata->gpio_release();
- msm_spi_free_gpios(dd);
-
-err_setup_gpio:
if (dd->use_rlock)
remote_mutex_unlock(&dd->r_lock);
+
+ /* Counter-part of system-resume when runtime-pm is not enabled. */
+ if (!pm_runtime_enabled(dd->dev))
+ msm_spi_pm_suspend_runtime(dd->dev);
+
mutex_unlock(&dd->core_lock);
+
+ pm_runtime_mark_last_busy(dd->dev);
+ pm_runtime_put_autosuspend(dd->dev);
+
err_setup_exit:
return rc;
}
@@ -2163,7 +2123,7 @@
clk_enabled = 0;
pclk_enabled = 0;
- dd->suspended = 0;
+ dd->suspended = 1;
dd->transfer_pending = 0;
dd->multi_xfr = 0;
dd->mode = SPI_MODE_NONE;
@@ -2179,6 +2139,10 @@
mutex_unlock(&dd->core_lock);
locked = 0;
+ pm_runtime_set_autosuspend_delay(&pdev->dev, MSEC_PER_SEC);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
rc = spi_register_master(master);
if (rc)
goto err_probe_reg_master;
@@ -2196,6 +2160,7 @@
err_attrs:
spi_unregister_master(master);
err_probe_reg_master:
+ pm_runtime_disable(&pdev->dev);
err_probe_irq:
err_probe_state:
msm_spi_teardown_dma(dd);
@@ -2228,48 +2193,130 @@
}
#ifdef CONFIG_PM
-static int msm_spi_suspend(struct platform_device *pdev, pm_message_t state)
+static int msm_spi_pm_suspend_runtime(struct device *device)
{
+ struct platform_device *pdev = to_platform_device(device);
struct spi_master *master = platform_get_drvdata(pdev);
- struct msm_spi *dd;
- unsigned long flags;
+ struct msm_spi *dd;
+ unsigned long flags;
+ dev_dbg(device, "pm_runtime: suspending...\n");
if (!master)
goto suspend_exit;
dd = spi_master_get_devdata(master);
if (!dd)
goto suspend_exit;
- /* Make sure nothing is added to the queue while we're suspending */
+ if (dd->suspended)
+ return 0;
+
+ /*
+ * Make sure nothing is added to the queue while we're
+ * suspending
+ */
spin_lock_irqsave(&dd->queue_lock, flags);
dd->suspended = 1;
spin_unlock_irqrestore(&dd->queue_lock, flags);
/* Wait for transactions to end, or time out */
- wait_event_interruptible(dd->continue_suspend, !dd->transfer_pending);
+ wait_event_interruptible(dd->continue_suspend,
+ !dd->transfer_pending);
+ msm_spi_disable_irqs(dd);
+ clk_disable_unprepare(dd->clk);
+ clk_disable_unprepare(dd->pclk);
+
+ /* Free the spi clk, miso, mosi, cs gpio */
+ if (dd->pdata && dd->pdata->gpio_release)
+ dd->pdata->gpio_release();
+
+ msm_spi_free_gpios(dd);
+
+ if (pm_qos_request_active(&qos_req_list))
+ pm_qos_update_request(&qos_req_list,
+ PM_QOS_DEFAULT_VALUE);
suspend_exit:
return 0;
}
-static int msm_spi_resume(struct platform_device *pdev)
+static int msm_spi_pm_resume_runtime(struct device *device)
{
+ struct platform_device *pdev = to_platform_device(device);
struct spi_master *master = platform_get_drvdata(pdev);
- struct msm_spi *dd;
+ struct msm_spi *dd;
+ int ret = 0;
+ dev_dbg(device, "pm_runtime: resuming...\n");
if (!master)
goto resume_exit;
dd = spi_master_get_devdata(master);
if (!dd)
goto resume_exit;
+ if (!dd->suspended)
+ return 0;
+
+ if (pm_qos_request_active(&qos_req_list))
+ pm_qos_update_request(&qos_req_list,
+ dd->pm_lat);
+
+ /* Configure the spi clk, miso, mosi and cs gpio */
+ if (dd->pdata->gpio_config) {
+ ret = dd->pdata->gpio_config();
+ if (ret) {
+ dev_err(dd->dev,
+ "%s: error configuring GPIOs\n",
+ __func__);
+ return ret;
+ }
+ }
+
+ ret = msm_spi_request_gpios(dd);
+ if (ret)
+ return ret;
+
+ clk_prepare_enable(dd->clk);
+ clk_prepare_enable(dd->pclk);
+ msm_spi_enable_irqs(dd);
dd->suspended = 0;
resume_exit:
return 0;
}
+
+static int msm_spi_suspend(struct device *device)
+{
+ if (!pm_runtime_enabled(device) || !pm_runtime_suspended(device)) {
+ struct platform_device *pdev = to_platform_device(device);
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct msm_spi *dd;
+
+ dev_dbg(device, "system suspend");
+ if (!master)
+ goto suspend_exit;
+ dd = spi_master_get_devdata(master);
+ if (!dd)
+ goto suspend_exit;
+ msm_spi_pm_suspend_runtime(device);
+ }
+suspend_exit:
+ return 0;
+}
+
+static int msm_spi_resume(struct device *device)
+{
+ /*
+ * Rely on runtime-PM to call resume in case it is enabled
+ * Even if it's not enabled, rely on 1st client transaction to do
+ * clock ON and gpio configuration
+ */
+ dev_dbg(device, "system resume");
+ return 0;
+}
#else
#define msm_spi_suspend NULL
#define msm_spi_resume NULL
+#define msm_spi_pm_suspend_runtime NULL
+#define msm_spi_pm_resume_runtime NULL
#endif /* CONFIG_PM */
static int __devexit msm_spi_remove(struct platform_device *pdev)
@@ -2283,6 +2330,8 @@
msm_spi_teardown_dma(dd);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
clk_put(dd->clk);
clk_put(dd->pclk);
destroy_workqueue(dd->workqueue);
@@ -2300,14 +2349,19 @@
{}
};
+static const struct dev_pm_ops msm_spi_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(msm_spi_suspend, msm_spi_resume)
+ SET_RUNTIME_PM_OPS(msm_spi_pm_suspend_runtime,
+ msm_spi_pm_resume_runtime, NULL)
+};
+
static struct platform_driver msm_spi_driver = {
.driver = {
.name = SPI_DRV_NAME,
.owner = THIS_MODULE,
+ .pm = &msm_spi_dev_pm_ops,
.of_match_table = msm_spi_dt_match,
},
- .suspend = msm_spi_suspend,
- .resume = msm_spi_resume,
.remove = __exit_p(msm_spi_remove),
};