diff mbox series

[v3,15/17] spi: spi-qcom-qspi: Use OPP API to set clk/perf state

Message ID 1588080785-6812-16-git-send-email-rnayak@codeaurora.org
State New
Headers show
Series None | expand

Commit Message

Rajendra Nayak April 28, 2020, 1:33 p.m. UTC 
QSPI needs to vote on a performance state of a power domain depending on
the clock rate. Add support for it by specifying the perf state/clock rate
as an OPP table in device tree.

Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Alok Chauhan <alokc@codeaurora.org>
Cc: Akash Asthana <akashast@codeaurora.org>
Cc: linux-spi@vger.kernel.org
---
 drivers/spi/spi-qcom-qspi.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/spi/spi-qcom-qspi.c b/drivers/spi/spi-qcom-qspi.c
index 3c4f83b..724a658 100644
--- a/drivers/spi/spi-qcom-qspi.c
+++ b/drivers/spi/spi-qcom-qspi.c
@@ -8,6 +8,7 @@ 
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <linux/pm_runtime.h>
+#include <linux/pm_opp.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/spi-mem.h>
 
@@ -139,6 +140,8 @@  struct qcom_qspi {
 	struct device *dev;
 	struct clk_bulk_data *clks;
 	struct qspi_xfer xfer;
+	struct opp_table *opp_table;
+	bool has_opp_table;
 	/* Lock to protect xfer and IRQ accessed registers */
 	spinlock_t lock;
 };
@@ -235,7 +238,7 @@  static int qcom_qspi_transfer_one(struct spi_master *master,
 		speed_hz = xfer->speed_hz;
 
 	/* In regular operation (SBL_EN=1) core must be 4x transfer clock */
-	ret = clk_set_rate(ctrl->clks[QSPI_CLK_CORE].clk, speed_hz * 4);
+	ret = dev_pm_opp_set_rate(ctrl->dev, speed_hz * 4);
 	if (ret) {
 		dev_err(ctrl->dev, "Failed to set core clk %d\n", ret);
 		return ret;
@@ -481,6 +484,20 @@  static int qcom_qspi_probe(struct platform_device *pdev)
 	master->handle_err = qcom_qspi_handle_err;
 	master->auto_runtime_pm = true;
 
+	ctrl->opp_table = dev_pm_opp_set_clkname(&pdev->dev, "core");
+	if (IS_ERR(ctrl->opp_table)) {
+		ret = PTR_ERR(ctrl->opp_table);
+		goto exit_probe_master_put;
+	}
+	/* OPP table is optional */
+	ret = dev_pm_opp_of_add_table(&pdev->dev);
+	if (!ret) {
+		ctrl->has_opp_table = true;
+	} else if (ret != -ENODEV) {
+		dev_err(&pdev->dev, "Invalid OPP table in Device tree\n");
+		return ret;
+	}
+
 	pm_runtime_enable(dev);
 
 	ret = spi_register_master(master);
@@ -488,6 +505,9 @@  static int qcom_qspi_probe(struct platform_device *pdev)
 		return 0;
 
 	pm_runtime_disable(dev);
+	if (ctrl->has_opp_table)
+		dev_pm_opp_of_remove_table(&pdev->dev);
+	dev_pm_opp_put_clkname(ctrl->opp_table);
 
 exit_probe_master_put:
 	spi_master_put(master);
@@ -498,6 +518,11 @@  static int qcom_qspi_probe(struct platform_device *pdev)
 static int qcom_qspi_remove(struct platform_device *pdev)
 {
 	struct spi_master *master = platform_get_drvdata(pdev);
+	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
+
+	if (ctrl->has_opp_table)
+		dev_pm_opp_of_remove_table(&pdev->dev);
+	dev_pm_opp_put_clkname(ctrl->opp_table);
 
 	/* Unregister _before_ disabling pm_runtime() so we stop transfers */
 	spi_unregister_master(master);
@@ -512,6 +537,8 @@  static int __maybe_unused qcom_qspi_runtime_suspend(struct device *dev)
 	struct spi_master *master = dev_get_drvdata(dev);
 	struct qcom_qspi *ctrl = spi_master_get_devdata(master);
 
+	/* Drop the performance state vote */
+	dev_pm_opp_set_rate(dev, 0);
 	clk_bulk_disable_unprepare(QSPI_NUM_CLKS, ctrl->clks);
 
 	return 0;