[V2] spi: spi-cadence-quadspi: add runtime pm support

Commit Message

Dhruva Gole Aug. 29, 2023, 6:27 a.m. UTC

Add runtime pm support to cadence-qspi driver, this allows the driver to
suspend whenever it's is not actively being used thus reducing active
power consumed by the system.

Also, with the use of devm_pm_runtime_enable we no longer need the
fallback probe_pm_failed that used to pm_runtime_disable

Co-developed-by: Apurva Nandan <[e-mail]>
Signed-off-by: Apurva Nandan <[e-mail]>
Signed-off-by: Dhruva Gole <[e-mail]>
---

Previous patch was marked RFT, and can be found here [0].
Tested [1] this patch on a TI SK-AM62 EVM having an OSPI NOR flash on board.

Changelog:
* Drop the DT patch as it had some comments that I am planning to
address at a later point.
* Add a ret val check for the pm_runtime_resume_and_get function call in
the exec_mem_op in case it reports any failures.

[0] https://lore.kernel.org/all/[e-mail]/
[1] https://gist.github.com/DhruvaG2000/7728ec09ae49c8c0d44d8e99de6795d5

Cc: Sai Krishna Potthuri <[e-mail]>
Cc: Ian Abbott <[e-mail]>
Cc: William Qiu <[e-mail]>
Cc: Brad Larson <[e-mail]>
Cc: Pratyush Yadav <[e-mail]>
Cc: Vignesh Raghavendra <[e-mail]>
Cc: Vibhore Vardhan <[e-mail]>

 drivers/spi/spi-cadence-quadspi.c | 42 ++++++++++++++++++++++++-------
 1 file changed, 33 insertions(+), 9 deletions(-)

Comments

Mark Brown Sept. 12, 2023, 11:38 a.m. UTC | #1

On Tue, 29 Aug 2023 11:57:08 +0530, Dhruva Gole wrote:
> Add runtime pm support to cadence-qspi driver, this allows the driver to
> suspend whenever it's is not actively being used thus reducing active
> power consumed by the system.
> 
> Also, with the use of devm_pm_runtime_enable we no longer need the
> fallback probe_pm_failed that used to pm_runtime_disable
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: spi-cadence-quadspi: add runtime pm support
      commit: 0578a6dbfe7514db7134501cf93acc21cf13e479

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Patch

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index b50db71ac4cc..4828da4587c5 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -116,6 +116,9 @@  struct cqspi_driver_platdata {
 #define CQSPI_TIMEOUT_MS			500
 #define CQSPI_READ_TIMEOUT_MS			10
 
+/* Runtime_pm autosuspend delay */
+#define CQSPI_AUTOSUSPEND_TIMEOUT		2000
+
 #define CQSPI_DUMMY_CLKS_PER_BYTE		8
 #define CQSPI_DUMMY_BYTES_MAX			4
 #define CQSPI_DUMMY_CLKS_MAX			31
@@ -1407,8 +1410,20 @@  static int cqspi_mem_process(struct spi_mem *mem, const struct spi_mem_op *op)
 static int cqspi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
 {
 	int ret;
+	struct cqspi_st *cqspi = spi_master_get_devdata(mem->spi->master);
+	struct device *dev = &cqspi->pdev->dev;
+
+	ret = pm_runtime_resume_and_get(dev);
+	if (ret) {
+		dev_err(&mem->spi->dev, "resume failed with %d\n", ret);
+		return ret;
+	}
 
 	ret = cqspi_mem_process(mem, op);
+
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
 	if (ret)
 		dev_err(&mem->spi->dev, "operation failed with %d\n", ret);
 
@@ -1753,10 +1768,10 @@  static int cqspi_probe(struct platform_device *pdev)
 	if (irq < 0)
 		return -ENXIO;
 
-	pm_runtime_enable(dev);
-	ret = pm_runtime_resume_and_get(dev);
-	if (ret < 0)
-		goto probe_pm_failed;
+	ret = pm_runtime_set_active(dev);
+	if (ret)
+		return ret;
+
 
 	ret = clk_prepare_enable(cqspi->clk);
 	if (ret) {
@@ -1862,21 +1877,29 @@  static int cqspi_probe(struct platform_device *pdev)
 			goto probe_setup_failed;
 	}
 
+	ret = devm_pm_runtime_enable(dev);
+	if (ret)
+		return ret;
+
+	pm_runtime_set_autosuspend_delay(dev, CQSPI_AUTOSUSPEND_TIMEOUT);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_get_noresume(dev);
+
 	ret = spi_register_controller(host);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to register SPI ctlr %d\n", ret);
 		goto probe_setup_failed;
 	}
 
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
+
 	return 0;
 probe_setup_failed:
 	cqspi_controller_enable(cqspi, 0);
 probe_reset_failed:
 	clk_disable_unprepare(cqspi->clk);
 probe_clk_failed:
-	pm_runtime_put_sync(dev);
-probe_pm_failed:
-	pm_runtime_disable(dev);
 	return ret;
 }
 
@@ -1928,7 +1951,8 @@  static int cqspi_resume(struct device *dev)
 	return spi_controller_resume(host);
 }
 
-static DEFINE_SIMPLE_DEV_PM_OPS(cqspi_dev_pm_ops, cqspi_suspend, cqspi_resume);
+static DEFINE_RUNTIME_DEV_PM_OPS(cqspi_dev_pm_ops, cqspi_suspend,
+				 cqspi_resume, NULL);
 
 static const struct cqspi_driver_platdata cdns_qspi = {
 	.quirks = CQSPI_DISABLE_DAC_MODE,
@@ -2012,7 +2036,7 @@  static struct platform_driver cqspi_platform_driver = {
 	.remove_new = cqspi_remove,
 	.driver = {
 		.name = CQSPI_NAME,
-		.pm = &cqspi_dev_pm_ops,
+		.pm = pm_ptr(&cqspi_dev_pm_ops),
 		.of_match_table = cqspi_dt_ids,
 	},
 };