[PATCH 09/10] drm/i915/spi: wake card on operations

[Alexander Usyskin <alexander.usyskin@xxxxxxxxx>]

Enable runtime PM in spi driver to notify i915 that
whole card should be kept awake while spi operations are
performed through this driver.

CC: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
---
 drivers/gpu/drm/i915/spi/intel_spi_drv.c | 44 ++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/drivers/gpu/drm/i915/spi/intel_spi_drv.c b/drivers/gpu/drm/i915/spi/intel_spi_drv.c
index 22b804ebadc0..6b514b137fd0 100644
--- a/drivers/gpu/drm/i915/spi/intel_spi_drv.c
+++ b/drivers/gpu/drm/i915/spi/intel_spi_drv.c
@@ -13,12 +13,15 @@
 #include <linux/sizes.h>
 #include <linux/io-64-nonatomic-lo-hi.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 #include "spi/intel_spi.h"
 #include "i915_reg_defs.h"
 
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/partitions.h>
 
+#define I915_SPI_RPM_TIMEOUT 500
+
 struct i915_spi {
 	struct kref refcnt;
 	struct mtd_info mtd;
@@ -473,6 +476,12 @@ static int i915_spi_erase(struct mtd_info *mtd, struct erase_info *info)
 	total_len = info->len;
 	addr = info->addr;
 
+	ret = pm_runtime_resume_and_get(mtd->dev.parent);
+	if (ret < 0) {
+		dev_err(&mtd->dev, "rpm: get failed %d\n", ret);
+		return ret;
+	}
+
 	mutex_lock(&spi->lock);
 
 	while (total_len > 0) {
@@ -514,6 +523,8 @@ static int i915_spi_erase(struct mtd_info *mtd, struct erase_info *info)
 
 out:
 	mutex_unlock(&spi->lock);
+	pm_runtime_mark_last_busy(mtd->dev.parent);
+	pm_runtime_put_autosuspend(mtd->dev.parent);
 	return ret;
 }
 
@@ -547,6 +558,12 @@ static int i915_spi_read(struct mtd_info *mtd, loff_t from, size_t len,
 	if (len > spi->regions[idx].size - from)
 		len = spi->regions[idx].size - from;
 
+	ret = pm_runtime_resume_and_get(mtd->dev.parent);
+	if (ret < 0) {
+		dev_err(&mtd->dev, "rpm: get failed %zd\n", ret);
+		return ret;
+	}
+
 	mutex_lock(&spi->lock);
 
 	ret = spi_read(spi, region, from, len, buf);
@@ -559,6 +576,8 @@ static int i915_spi_read(struct mtd_info *mtd, loff_t from, size_t len,
 	*retlen = ret;
 
 	mutex_unlock(&spi->lock);
+	pm_runtime_mark_last_busy(mtd->dev.parent);
+	pm_runtime_put_autosuspend(mtd->dev.parent);
 	return 0;
 }
 
@@ -592,6 +611,12 @@ static int i915_spi_write(struct mtd_info *mtd, loff_t to, size_t len,
 	if (len > spi->regions[idx].size - to)
 		len = spi->regions[idx].size - to;
 
+	ret = pm_runtime_resume_and_get(mtd->dev.parent);
+	if (ret < 0) {
+		dev_err(&mtd->dev, "rpm: get failed %zd\n", ret);
+		return ret;
+	}
+
 	mutex_lock(&spi->lock);
 
 	ret = spi_write(spi, region, to, len, buf);
@@ -604,6 +629,8 @@ static int i915_spi_write(struct mtd_info *mtd, loff_t to, size_t len,
 	*retlen = ret;
 
 	mutex_unlock(&spi->lock);
+	pm_runtime_mark_last_busy(mtd->dev.parent);
+	pm_runtime_put_autosuspend(mtd->dev.parent);
 	return 0;
 }
 
@@ -749,6 +776,17 @@ static int i915_spi_probe(struct auxiliary_device *aux_dev,
 		}
 	}
 
+	pm_runtime_enable(device);
+
+	pm_runtime_set_autosuspend_delay(device, I915_SPI_RPM_TIMEOUT);
+	pm_runtime_use_autosuspend(device);
+
+	ret = pm_runtime_resume_and_get(device);
+	if (ret < 0) {
+		dev_err(device, "rpm: get failed %d\n", ret);
+		goto err_norpm;
+	}
+
 	spi->base = devm_ioremap_resource(device, &ispi->bar);
 	if (IS_ERR(spi->base)) {
 		dev_err(device, "mmio not mapped\n");
@@ -773,9 +811,13 @@ static int i915_spi_probe(struct auxiliary_device *aux_dev,
 
 	dev_dbg(device, "i915-spi is bound\n");
 
+	pm_runtime_put(device);
 	return 0;
 
 err:
+	pm_runtime_put(device);
+err_norpm:
+	pm_runtime_disable(device);
 	kref_put(&spi->refcnt, i915_spi_release);
 	return ret;
 }
@@ -787,6 +829,8 @@ static void i915_spi_remove(struct auxiliary_device *aux_dev)
 	if (!spi)
 		return;
 
+	pm_runtime_disable(&aux_dev->dev);
+
 	mtd_device_unregister(&spi->mtd);
 
 	dev_set_drvdata(&aux_dev->dev, NULL);
-- 
2.34.1