1 files changed, 87 insertions, 48 deletions

diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c
index 84fb35f6837f..88192c25c44c 100644
--- a/drivers/i2c/busses/i2c-img-scb.c
+++ b/drivers/i2c/busses/i2c-img-scb.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * I2C adapter for the IMG Serial Control Bus (SCB) IP block.
  *
  * Copyright (C) 2009, 2010, 2012, 2014 Imagination Technologies Ltd.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  * There are three ways that this I2C controller can be driven:
  *
  * - Raw control of the SDA and SCK signals.
@@ -82,6 +79,7 @@
 #include <linux/module.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 #include <linux/timer.h>
 
@@ -259,7 +257,7 @@
 #define IMG_I2C_TIMEOUT			(msecs_to_jiffies(1000))
 
 /*
- * Worst incs are 1 (innacurate) and 16*256 (irregular).
+ * Worst incs are 1 (inaccurate) and 16*256 (irregular).
  * So a sensible inc is the logarithmic mean: 64 (2^6), which is
  * in the middle of the valid range (0-127).
  */
@@ -280,6 +278,8 @@
 #define ISR_COMPLETE(err)	(ISR_COMPLETE_M | (ISR_STATUS_M & (err)))
 #define ISR_FATAL(err)		(ISR_COMPLETE(err) | ISR_FATAL_M)
 
+#define IMG_I2C_PM_TIMEOUT	1000 /* ms */
+
 enum img_i2c_mode {
 	MODE_INACTIVE,
 	MODE_RAW,
@@ -304,7 +304,7 @@ static struct img_i2c_timings timings[] = {
 	/* Standard mode */
 	{
 		.name = "standard",
-		.max_bitrate = 100000,
+		.max_bitrate = I2C_MAX_STANDARD_MODE_FREQ,
 		.tckh = 4000,
 		.tckl = 4700,
 		.tsdh = 4700,
@@ -316,7 +316,7 @@ static struct img_i2c_timings timings[] = {
 	/* Fast mode */
 	{
 		.name = "fast",
-		.max_bitrate = 400000,
+		.max_bitrate = I2C_MAX_FAST_MODE_FREQ,
 		.tckh = 600,
 		.tckl = 1300,
 		.tsdh = 600,
@@ -408,6 +408,9 @@ struct img_i2c {
 	unsigned int raw_timeout;
 };
 
+static int img_i2c_runtime_suspend(struct device *dev);
+static int img_i2c_runtime_resume(struct device *dev);
+
 static void img_i2c_writel(struct img_i2c *i2c, u32 offset, u32 value)
 {
 	writel(value, i2c->base + offset);
@@ -826,9 +829,9 @@ next_atomic_cmd:
  * Timer function to check if something has gone wrong in automatic mode (so we
  * don't have to handle so many interrupts just to catch an exception).
  */
-static void img_i2c_check_timer(unsigned long arg)
+static void img_i2c_check_timer(struct timer_list *t)
 {
-	struct img_i2c *i2c = (struct img_i2c *)arg;
+	struct img_i2c *i2c = timer_container_of(i2c, t, check_timer);
 	unsigned long flags;
 	unsigned int line_status;
 
@@ -910,7 +913,7 @@ static unsigned int img_i2c_auto(struct img_i2c *i2c,
 
 static irqreturn_t img_i2c_isr(int irq, void *dev_id)
 {
-	struct img_i2c *i2c = (struct img_i2c *)dev_id;
+	struct img_i2c *i2c = dev_id;
 	u32 int_status, line_status;
 	/* We handle transaction completion AFTER accessing registers */
 	unsigned int hret;
@@ -1054,8 +1057,8 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 			atomic = true;
 	}
 
-	ret = clk_prepare_enable(i2c->scb_clk);
-	if (ret)
+	ret = pm_runtime_resume_and_get(adap->dev.parent);
+	if (ret < 0)
 		return ret;
 
 	for (i = 0; i < num; i++) {
@@ -1119,19 +1122,16 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 
 		time_left = wait_for_completion_timeout(&i2c->msg_complete,
 						      IMG_I2C_TIMEOUT);
-		del_timer_sync(&i2c->check_timer);
+		timer_delete_sync(&i2c->check_timer);
 
-		if (time_left == 0) {
-			dev_err(adap->dev.parent, "i2c transfer timed out\n");
+		if (time_left == 0)
 			i2c->msg_status = -ETIMEDOUT;
-			break;
-		}
 
 		if (i2c->msg_status)
 			break;
 	}
 
-	clk_disable_unprepare(i2c->scb_clk);
+	pm_runtime_put_autosuspend(adap->dev.parent);
 
 	return i2c->msg_status ? i2c->msg_status : num;
 }
@@ -1142,19 +1142,20 @@ static u32 img_i2c_func(struct i2c_adapter *adap)
 }
 
 static const struct i2c_algorithm img_i2c_algo = {
-	.master_xfer = img_i2c_xfer,
+	.xfer = img_i2c_xfer,
 	.functionality = img_i2c_func,
 };
 
 static int img_i2c_init(struct img_i2c *i2c)
 {
 	unsigned int clk_khz, bitrate_khz, clk_period, tckh, tckl, tsdh;
-	unsigned int i, ret, data, prescale, inc, int_bitrate, filt;
+	unsigned int i, data, prescale, inc, int_bitrate, filt;
 	struct img_i2c_timings timing;
 	u32 rev;
+	int ret;
 
-	ret = clk_prepare_enable(i2c->scb_clk);
-	if (ret)
+	ret = pm_runtime_resume_and_get(i2c->adap.dev.parent);
+	if (ret < 0)
 		return ret;
 
 	rev = img_i2c_readl(i2c, SCB_CORE_REV_REG);
@@ -1163,7 +1164,7 @@ static int img_i2c_init(struct img_i2c *i2c)
 			 "Unknown hardware revision (%d.%d.%d.%d)\n",
 			 (rev >> 24) & 0xff, (rev >> 16) & 0xff,
 			 (rev >> 8) & 0xff, rev & 0xff);
-		clk_disable_unprepare(i2c->scb_clk);
+		pm_runtime_put_autosuspend(i2c->adap.dev.parent);
 		return -EINVAL;
 	}
 
@@ -1314,7 +1315,7 @@ static int img_i2c_init(struct img_i2c *i2c)
 	/* Perform a synchronous sequence to reset the bus */
 	ret = img_i2c_reset_bus(i2c);
 
-	clk_disable_unprepare(i2c->scb_clk);
+	pm_runtime_put_autosuspend(i2c->adap.dev.parent);
 
 	return ret;
 }
@@ -1323,7 +1324,6 @@ static int img_i2c_probe(struct platform_device *pdev)
 {
 	struct device_node *node = pdev->dev.of_node;
 	struct img_i2c *i2c;
-	struct resource *res;
 	int irq, ret;
 	u32 val;
 
@@ -1331,16 +1331,13 @@ static int img_i2c_probe(struct platform_device *pdev)
 	if (!i2c)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	i2c->base = devm_ioremap_resource(&pdev->dev, res);
+	i2c->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(i2c->base))
 		return PTR_ERR(i2c->base);
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq < 0) {
-		dev_err(&pdev->dev, "can't get irq number\n");
+	if (irq < 0)
 		return irq;
-	}
 
 	i2c->sys_clk = devm_clk_get(&pdev->dev, "sys");
 	if (IS_ERR(i2c->sys_clk)) {
@@ -1362,8 +1359,7 @@ static int img_i2c_probe(struct platform_device *pdev)
 	}
 
 	/* Set up the exception check timer */
-	setup_timer(&i2c->check_timer, img_i2c_check_timer,
-		    (unsigned long)i2c);
+	timer_setup(&i2c->check_timer, img_i2c_check_timer, 0);
 
 	i2c->bitrate = timings[0].max_bitrate;
 	if (!of_property_read_u32(node, "clock-frequency", &val))
@@ -1384,43 +1380,84 @@ static int img_i2c_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, i2c);
 
-	ret = clk_prepare_enable(i2c->sys_clk);
-	if (ret)
-		return ret;
+	pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_I2C_PM_TIMEOUT);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+	if (!pm_runtime_enabled(&pdev->dev)) {
+		ret = img_i2c_runtime_resume(&pdev->dev);
+		if (ret)
+			return ret;
+	}
 
 	ret = img_i2c_init(i2c);
 	if (ret)
-		goto disable_clk;
+		goto rpm_disable;
 
 	ret = i2c_add_numbered_adapter(&i2c->adap);
 	if (ret < 0)
-		goto disable_clk;
+		goto rpm_disable;
 
 	return 0;
 
-disable_clk:
-	clk_disable_unprepare(i2c->sys_clk);
+rpm_disable:
+	if (!pm_runtime_enabled(&pdev->dev))
+		img_i2c_runtime_suspend(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	return ret;
 }
 
-static int img_i2c_remove(struct platform_device *dev)
+static void img_i2c_remove(struct platform_device *dev)
 {
 	struct img_i2c *i2c = platform_get_drvdata(dev);
 
 	i2c_del_adapter(&i2c->adap);
+	pm_runtime_disable(&dev->dev);
+	if (!pm_runtime_status_suspended(&dev->dev))
+		img_i2c_runtime_suspend(&dev->dev);
+}
+
+static int img_i2c_runtime_suspend(struct device *dev)
+{
+	struct img_i2c *i2c = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(i2c->scb_clk);
 	clk_disable_unprepare(i2c->sys_clk);
 
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
+static int img_i2c_runtime_resume(struct device *dev)
+{
+	struct img_i2c *i2c = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(i2c->sys_clk);
+	if (ret) {
+		dev_err(dev, "Unable to enable sys clock\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(i2c->scb_clk);
+	if (ret) {
+		dev_err(dev, "Unable to enable scb clock\n");
+		clk_disable_unprepare(i2c->sys_clk);
+		return ret;
+	}
+
+	return 0;
+}
+
 static int img_i2c_suspend(struct device *dev)
 {
 	struct img_i2c *i2c = dev_get_drvdata(dev);
+	int ret;
 
-	img_i2c_switch_mode(i2c, MODE_SUSPEND);
+	ret = pm_runtime_force_suspend(dev);
+	if (ret)
+		return ret;
 
-	clk_disable_unprepare(i2c->sys_clk);
+	img_i2c_switch_mode(i2c, MODE_SUSPEND);
 
 	return 0;
 }
@@ -1430,7 +1467,7 @@ static int img_i2c_resume(struct device *dev)
 	struct img_i2c *i2c = dev_get_drvdata(dev);
 	int ret;
 
-	ret = clk_prepare_enable(i2c->sys_clk);
+	ret = pm_runtime_force_resume(dev);
 	if (ret)
 		return ret;
 
@@ -1438,9 +1475,11 @@ static int img_i2c_resume(struct device *dev)
 
 	return 0;
 }
-#endif /* CONFIG_PM_SLEEP */
 
-static SIMPLE_DEV_PM_OPS(img_i2c_pm, img_i2c_suspend, img_i2c_resume);
+static const struct dev_pm_ops img_i2c_pm = {
+	RUNTIME_PM_OPS(img_i2c_runtime_suspend, img_i2c_runtime_resume, NULL)
+	SYSTEM_SLEEP_PM_OPS(img_i2c_suspend, img_i2c_resume)
+};
 
 static const struct of_device_id img_scb_i2c_match[] = {
 	{ .compatible = "img,scb-i2c" },
@@ -1452,13 +1491,13 @@ static struct platform_driver img_scb_i2c_driver = {
 	.driver = {
 		.name		= "img-i2c-scb",
 		.of_match_table	= img_scb_i2c_match,
-		.pm		= &img_i2c_pm,
+		.pm		= pm_ptr(&img_i2c_pm),
 	},
 	.probe = img_i2c_probe,
 	.remove = img_i2c_remove,
 };
 module_platform_driver(img_scb_i2c_driver);
 
-MODULE_AUTHOR("James Hogan <james.hogan@imgtec.com>");
+MODULE_AUTHOR("James Hogan <jhogan@kernel.org>");
 MODULE_DESCRIPTION("IMG host I2C driver");
 MODULE_LICENSE("GPL v2");