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path: root/drivers/bus/sunxi-rsb.c
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Diffstat (limited to 'drivers/bus/sunxi-rsb.c')
-rw-r--r--drivers/bus/sunxi-rsb.c117
1 files changed, 58 insertions, 59 deletions
diff --git a/drivers/bus/sunxi-rsb.c b/drivers/bus/sunxi-rsb.c
index 4566e730ef2b..82735c58be11 100644
--- a/drivers/bus/sunxi-rsb.c
+++ b/drivers/bus/sunxi-rsb.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* RSB (Reduced Serial Bus) driver.
*
* Author: Chen-Yu Tsai <wens@csie.org>
*
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
- *
* The RSB controller looks like an SMBus controller which only supports
* byte and word data transfers. But, it differs from standard SMBus
* protocol on several aspects:
@@ -31,7 +28,6 @@
* This document is officially released by Allwinner.
*
* This driver is based on i2c-sun6i-p2wi.c, the P2WI bus driver.
- *
*/
#include <linux/clk.h>
@@ -43,7 +39,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
-#include <linux/of_platform.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
@@ -132,9 +128,9 @@ struct sunxi_rsb {
};
/* bus / slave device related functions */
-static struct bus_type sunxi_rsb_bus;
+static const struct bus_type sunxi_rsb_bus;
-static int sunxi_rsb_device_match(struct device *dev, struct device_driver *drv)
+static int sunxi_rsb_device_match(struct device *dev, const struct device_driver *drv)
{
return of_driver_match_device(dev, drv);
}
@@ -176,12 +172,17 @@ static void sunxi_rsb_device_remove(struct device *dev)
drv->remove(to_sunxi_rsb_device(dev));
}
-static struct bus_type sunxi_rsb_bus = {
+static int sunxi_rsb_device_modalias(const struct device *dev, struct kobj_uevent_env *env)
+{
+ return of_device_uevent_modalias(dev, env);
+}
+
+static const struct bus_type sunxi_rsb_bus = {
.name = RSB_CTRL_NAME,
.match = sunxi_rsb_device_match,
.probe = sunxi_rsb_device_probe,
.remove = sunxi_rsb_device_remove,
- .uevent = of_device_uevent_modalias,
+ .uevent = sunxi_rsb_device_modalias,
};
static void sunxi_rsb_dev_release(struct device *dev)
@@ -227,6 +228,8 @@ static struct sunxi_rsb_device *sunxi_rsb_device_create(struct sunxi_rsb *rsb,
dev_dbg(&rdev->dev, "device %s registered\n", dev_name(&rdev->dev));
+ return rdev;
+
err_device_add:
put_device(&rdev->dev);
@@ -269,6 +272,9 @@ EXPORT_SYMBOL_GPL(sunxi_rsb_driver_register);
/* common code that starts a transfer */
static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb)
{
+ u32 int_mask, status;
+ bool timeout;
+
if (readl(rsb->regs + RSB_CTRL) & RSB_CTRL_START_TRANS) {
dev_dbg(rsb->dev, "RSB transfer still in progress\n");
return -EBUSY;
@@ -276,13 +282,23 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb)
reinit_completion(&rsb->complete);
- writel(RSB_INTS_LOAD_BSY | RSB_INTS_TRANS_ERR | RSB_INTS_TRANS_OVER,
- rsb->regs + RSB_INTE);
+ int_mask = RSB_INTS_LOAD_BSY | RSB_INTS_TRANS_ERR | RSB_INTS_TRANS_OVER;
+ writel(int_mask, rsb->regs + RSB_INTE);
writel(RSB_CTRL_START_TRANS | RSB_CTRL_GLOBAL_INT_ENB,
rsb->regs + RSB_CTRL);
- if (!wait_for_completion_io_timeout(&rsb->complete,
- msecs_to_jiffies(100))) {
+ if (irqs_disabled()) {
+ timeout = readl_poll_timeout_atomic(rsb->regs + RSB_INTS,
+ status, (status & int_mask),
+ 10, 100000);
+ writel(status, rsb->regs + RSB_INTS);
+ } else {
+ timeout = !wait_for_completion_io_timeout(&rsb->complete,
+ msecs_to_jiffies(100));
+ status = rsb->status;
+ }
+
+ if (timeout) {
dev_dbg(rsb->dev, "RSB timeout\n");
/* abort the transfer */
@@ -294,18 +310,18 @@ static int _sunxi_rsb_run_xfer(struct sunxi_rsb *rsb)
return -ETIMEDOUT;
}
- if (rsb->status & RSB_INTS_LOAD_BSY) {
+ if (status & RSB_INTS_LOAD_BSY) {
dev_dbg(rsb->dev, "RSB busy\n");
return -EBUSY;
}
- if (rsb->status & RSB_INTS_TRANS_ERR) {
- if (rsb->status & RSB_INTS_TRANS_ERR_ACK) {
+ if (status & RSB_INTS_TRANS_ERR) {
+ if (status & RSB_INTS_TRANS_ERR_ACK) {
dev_dbg(rsb->dev, "RSB slave nack\n");
return -EINVAL;
}
- if (rsb->status & RSB_INTS_TRANS_ERR_DATA) {
+ if (status & RSB_INTS_TRANS_ERR_DATA) {
dev_dbg(rsb->dev, "RSB transfer data error\n");
return -EIO;
}
@@ -357,7 +373,6 @@ static int sunxi_rsb_read(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr,
unlock:
mutex_unlock(&rsb->lock);
- pm_runtime_mark_last_busy(rsb->dev);
pm_runtime_put_autosuspend(rsb->dev);
return ret;
@@ -401,7 +416,6 @@ static int sunxi_rsb_write(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr,
mutex_unlock(&rsb->lock);
- pm_runtime_mark_last_busy(rsb->dev);
pm_runtime_put_autosuspend(rsb->dev);
return ret;
@@ -441,7 +455,7 @@ static void regmap_sunxi_rsb_free_ctx(void *context)
kfree(ctx);
}
-static struct regmap_bus regmap_sunxi_rsb = {
+static const struct regmap_bus regmap_sunxi_rsb = {
.reg_write = regmap_sunxi_rsb_reg_write,
.reg_read = regmap_sunxi_rsb_reg_read,
.free_context = regmap_sunxi_rsb_free_ctx,
@@ -730,18 +744,15 @@ static int sunxi_rsb_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
- struct resource *r;
struct sunxi_rsb *rsb;
u32 clk_freq = 3000000;
int irq, ret;
of_property_read_u32(np, "clock-frequency", &clk_freq);
- if (clk_freq > RSB_MAX_FREQ) {
- dev_err(dev,
- "clock-frequency (%u Hz) is too high (max = 20MHz)\n",
- clk_freq);
- return -EINVAL;
- }
+ if (clk_freq > RSB_MAX_FREQ)
+ return dev_err_probe(dev, -EINVAL,
+ "clock-frequency (%u Hz) is too high (max = 20MHz)\n",
+ clk_freq);
rsb = devm_kzalloc(dev, sizeof(*rsb), GFP_KERNEL);
if (!rsb)
@@ -750,8 +761,7 @@ static int sunxi_rsb_probe(struct platform_device *pdev)
rsb->dev = dev;
rsb->clk_freq = clk_freq;
platform_set_drvdata(pdev, rsb);
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- rsb->regs = devm_ioremap_resource(dev, r);
+ rsb->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(rsb->regs))
return PTR_ERR(rsb->regs);
@@ -760,28 +770,22 @@ static int sunxi_rsb_probe(struct platform_device *pdev)
return irq;
rsb->clk = devm_clk_get(dev, NULL);
- if (IS_ERR(rsb->clk)) {
- ret = PTR_ERR(rsb->clk);
- dev_err(dev, "failed to retrieve clk: %d\n", ret);
- return ret;
- }
+ if (IS_ERR(rsb->clk))
+ return dev_err_probe(dev, PTR_ERR(rsb->clk),
+ "failed to retrieve clk\n");
rsb->rstc = devm_reset_control_get(dev, NULL);
- if (IS_ERR(rsb->rstc)) {
- ret = PTR_ERR(rsb->rstc);
- dev_err(dev, "failed to retrieve reset controller: %d\n", ret);
- return ret;
- }
+ if (IS_ERR(rsb->rstc))
+ return dev_err_probe(dev, PTR_ERR(rsb->rstc),
+ "failed to retrieve reset controller\n");
init_completion(&rsb->complete);
mutex_init(&rsb->lock);
ret = devm_request_irq(dev, irq, sunxi_rsb_irq, 0, RSB_CTRL_NAME, rsb);
- if (ret) {
- dev_err(dev, "can't register interrupt handler irq %d: %d\n",
- irq, ret);
- return ret;
- }
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "can't register interrupt handler irq %d\n", irq);
ret = sunxi_rsb_hw_init(rsb);
if (ret)
@@ -803,23 +807,13 @@ static int sunxi_rsb_probe(struct platform_device *pdev)
return 0;
}
-static int sunxi_rsb_remove(struct platform_device *pdev)
+static void sunxi_rsb_remove(struct platform_device *pdev)
{
struct sunxi_rsb *rsb = platform_get_drvdata(pdev);
device_for_each_child(rsb->dev, NULL, sunxi_rsb_remove_devices);
pm_runtime_disable(&pdev->dev);
sunxi_rsb_hw_exit(rsb);
-
- return 0;
-}
-
-static void sunxi_rsb_shutdown(struct platform_device *pdev)
-{
- struct sunxi_rsb *rsb = platform_get_drvdata(pdev);
-
- pm_runtime_disable(&pdev->dev);
- sunxi_rsb_hw_exit(rsb);
}
static const struct dev_pm_ops sunxi_rsb_dev_pm_ops = {
@@ -836,8 +830,7 @@ MODULE_DEVICE_TABLE(of, sunxi_rsb_of_match_table);
static struct platform_driver sunxi_rsb_driver = {
.probe = sunxi_rsb_probe,
- .remove = sunxi_rsb_remove,
- .shutdown = sunxi_rsb_shutdown,
+ .remove = sunxi_rsb_remove,
.driver = {
.name = RSB_CTRL_NAME,
.of_match_table = sunxi_rsb_of_match_table,
@@ -855,7 +848,13 @@ static int __init sunxi_rsb_init(void)
return ret;
}
- return platform_driver_register(&sunxi_rsb_driver);
+ ret = platform_driver_register(&sunxi_rsb_driver);
+ if (ret) {
+ bus_unregister(&sunxi_rsb_bus);
+ return ret;
+ }
+
+ return 0;
}
module_init(sunxi_rsb_init);
generated by cgit (git 2.34.1) at 2025-12-25 22:51:28 +0000