spi: spi-nxp-fspi: enable runtime pm for fspi

Enable the runtime PM in fspi driver.
Also for system PM, On some board like i.MX8ULP-EVK board,
after system suspend, IOMUX module will lost power, so all
the pinctrl setting will lost when system resume back, need
driver to save/restore the pinctrl setting.

Signed-off-by: Han Xu <han.xu@nxp.com>
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Link: https://patch.msgid.link/20250428-flexspipatch-v3-2-61d5e8f591bc@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-nxp-fspi.c b/drivers/spi/spi-nxp-fspi.c
index 00da184be88a026bf562c9808e18e2335a0959e9..f7c3330a19009223cbffae8673d264246418e561 100644 (file)
--- a/drivers/spi/spi-nxp-fspi.c
+++ b/drivers/spi/spi-nxp-fspi.c
@@ -48,6 +48,8 @@
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pm_runtime.h>
 #include <linux/pm_qos.h>
 #include <linux/regmap.h>
 #include <linux/sizes.h>
@@ -57,6 +59,9 @@
 #include <linux/spi/spi.h>
 #include <linux/spi/spi-mem.h>
 
+/* runtime pm timeout */
+#define FSPI_RPM_TIMEOUT 50    /* 50ms */
+
 /* Registers used by the driver */
 #define FSPI_MCR0                      0x00
 #define FSPI_MCR0_AHB_TIMEOUT(x)       ((x) << 24)
@@ -394,6 +399,8 @@ struct nxp_fspi {
        struct mutex lock;
        struct pm_qos_request pm_qos_req;
        int selected;
+#define FSPI_NEED_INIT         (1 << 0)
+       int flags;
 };
 
 static inline int needs_ip_only(struct nxp_fspi *f)
@@ -927,6 +934,13 @@ static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
 
        mutex_lock(&f->lock);
 
+       err = pm_runtime_get_sync(f->dev);
+       if (err < 0) {
+               mutex_unlock(&f->lock);
+               dev_err(f->dev, "Failed to enable clock %d\n", __LINE__);
+               return err;
+       }
+
        /* Wait for controller being ready. */
        err = fspi_readl_poll_tout(f, f->iobase + FSPI_STS0,
                                   FSPI_STS0_ARB_IDLE, 1, POLL_TOUT, true);
@@ -955,8 +969,10 @@ static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
        /* Invalidate the data in the AHB buffer. */
        nxp_fspi_invalid(f);
 
-       mutex_unlock(&f->lock);
+       pm_runtime_mark_last_busy(f->dev);
+       pm_runtime_put_autosuspend(f->dev);
 
+       mutex_unlock(&f->lock);
        return err;
 }
 
@@ -1216,9 +1232,14 @@ static int nxp_fspi_probe(struct platform_device *pdev)
        if (irq < 0)
                return dev_err_probe(dev, irq, "Failed to get irq source");
 
-       ret = nxp_fspi_clk_prep_enable(f);
-       if (ret)
-               return dev_err_probe(dev, ret, "Can't enable the clock\n");
+       pm_runtime_enable(dev);
+       pm_runtime_set_autosuspend_delay(dev, FSPI_RPM_TIMEOUT);
+       pm_runtime_use_autosuspend(dev);
+
+       /* enable clock */
+       ret = pm_runtime_get_sync(f->dev);
+       if (ret < 0)
+               return dev_err_probe(dev, ret, "Failed to enable clock");
 
        /* Clear potential interrupts */
        reg = fspi_readl(f, f->iobase + FSPI_INTR);
@@ -1227,12 +1248,14 @@ static int nxp_fspi_probe(struct platform_device *pdev)
 
        nxp_fspi_default_setup(f);
 
+       ret = pm_runtime_put_sync(dev);
+       if (ret < 0)
+               return dev_err_probe(dev, ret, "Failed to disable clock");
+
        ret = devm_request_irq(dev, irq,
                        nxp_fspi_irq_handler, 0, pdev->name, f);
-       if (ret) {
-               nxp_fspi_clk_disable_unprep(f);
+       if (ret)
                return dev_err_probe(dev, ret, "Failed to request irq\n");
-       }
 
        devm_mutex_init(dev, &f->lock);
 
@@ -1249,29 +1272,70 @@ static void nxp_fspi_remove(struct platform_device *pdev)
 {
        struct nxp_fspi *f = platform_get_drvdata(pdev);
 
+       /* enable clock first since there is reigster access */
+       pm_runtime_get_sync(f->dev);
+
        /* disable the hardware */
        fspi_writel(f, FSPI_MCR0_MDIS, f->iobase + FSPI_MCR0);
 
+       pm_runtime_disable(f->dev);
+       pm_runtime_put_noidle(f->dev);
        nxp_fspi_clk_disable_unprep(f);
 
        if (f->ahb_addr)
                iounmap(f->ahb_addr);
 }
 
-static int nxp_fspi_suspend(struct device *dev)
+static int nxp_fspi_runtime_suspend(struct device *dev)
 {
+       struct nxp_fspi *f = dev_get_drvdata(dev);
+
+       nxp_fspi_clk_disable_unprep(f);
+
        return 0;
 }
 
-static int nxp_fspi_resume(struct device *dev)
+static int nxp_fspi_runtime_resume(struct device *dev)
 {
        struct nxp_fspi *f = dev_get_drvdata(dev);
+       int ret;
 
-       nxp_fspi_default_setup(f);
+       ret = nxp_fspi_clk_prep_enable(f);
+       if (ret)
+               return ret;
 
-       return 0;
+       if (f->flags & FSPI_NEED_INIT) {
+               nxp_fspi_default_setup(f);
+               ret = pinctrl_pm_select_default_state(dev);
+               if (ret)
+                       dev_err(dev, "select flexspi default pinctrl failed!\n");
+               f->flags &= ~FSPI_NEED_INIT;
+       }
+
+       return ret;
 }
 
+static int nxp_fspi_suspend(struct device *dev)
+{
+       struct nxp_fspi *f = dev_get_drvdata(dev);
+       int ret;
+
+       ret = pinctrl_pm_select_sleep_state(dev);
+       if (ret) {
+               dev_err(dev, "select flexspi sleep pinctrl failed!\n");
+               return ret;
+       }
+
+       f->flags |= FSPI_NEED_INIT;
+
+       return pm_runtime_force_suspend(dev);
+}
+
+static const struct dev_pm_ops nxp_fspi_pm_ops = {
+       RUNTIME_PM_OPS(nxp_fspi_runtime_suspend, nxp_fspi_runtime_resume, NULL)
+       SYSTEM_SLEEP_PM_OPS(nxp_fspi_suspend, pm_runtime_force_resume)
+};
+
 static const struct of_device_id nxp_fspi_dt_ids[] = {
        { .compatible = "nxp,lx2160a-fspi", .data = (void *)&lx2160a_data, },
        { .compatible = "nxp,imx8mm-fspi", .data = (void *)&imx8mm_data, },
@@ -1291,17 +1355,12 @@ static const struct acpi_device_id nxp_fspi_acpi_ids[] = {
 MODULE_DEVICE_TABLE(acpi, nxp_fspi_acpi_ids);
 #endif
 
-static const struct dev_pm_ops nxp_fspi_pm_ops = {
-       .suspend        = nxp_fspi_suspend,
-       .resume         = nxp_fspi_resume,
-};
-
 static struct platform_driver nxp_fspi_driver = {
        .driver = {
                .name   = "nxp-fspi",
                .of_match_table = nxp_fspi_dt_ids,
                .acpi_match_table = ACPI_PTR(nxp_fspi_acpi_ids),
-               .pm =   &nxp_fspi_pm_ops,
+               .pm = pm_ptr(&nxp_fspi_pm_ops),
        },
        .probe          = nxp_fspi_probe,
        .remove         = nxp_fspi_remove,