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Diffstat (limited to 'drivers/i2c/busses/i2c-st.c')
-rw-r--r--drivers/i2c/busses/i2c-st.c72
1 files changed, 26 insertions, 46 deletions
diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c
index 9e62f893958a..97d70e667227 100644
--- a/drivers/i2c/busses/i2c-st.c
+++ b/drivers/i2c/busses/i2c-st.c
@@ -1,13 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2013 STMicroelectronics
*
- * I2C master mode controller driver, used in STMicroelectronics devices.
+ * I2C controller driver, used in STMicroelectronics devices.
*
* Author: Maxime Coquelin <maxime.coquelin@st.com>
- *
- * 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.
*/
#include <linux/clk.h>
@@ -16,6 +13,7 @@
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/minmax.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -153,8 +151,8 @@ struct st_i2c_timings {
/**
* struct st_i2c_client - client specific data
- * @addr: 8-bit slave addr, including r/w bit
- * @count: number of bytes to be transfered
+ * @addr: 8-bit target addr, including r/w bit
+ * @count: number of bytes to be transferred
* @xfered: number of bytes already transferred
* @buf: data buffer
* @result: result of the transfer
@@ -216,7 +214,7 @@ static inline void st_i2c_clr_bits(void __iomem *reg, u32 mask)
*/
static struct st_i2c_timings i2c_timings[] = {
[I2C_MODE_STANDARD] = {
- .rate = 100000,
+ .rate = I2C_MAX_STANDARD_MODE_FREQ,
.rep_start_hold = 4400,
.rep_start_setup = 5170,
.start_hold = 4400,
@@ -225,7 +223,7 @@ static struct st_i2c_timings i2c_timings[] = {
.bus_free_time = 5170,
},
[I2C_MODE_FAST] = {
- .rate = 400000,
+ .rate = I2C_MAX_FAST_MODE_FREQ,
.rep_start_hold = 660,
.rep_start_setup = 660,
.start_hold = 660,
@@ -425,23 +423,20 @@ static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev)
tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
tx_fstat &= SSC_TX_FSTAT_STATUS;
- if (c->count < (SSC_TXFIFO_SIZE - tx_fstat))
- i = c->count;
- else
- i = SSC_TXFIFO_SIZE - tx_fstat;
-
- for (; i > 0; i--, c->count--, c->buf++)
+ for (i = min(c->count, SSC_TXFIFO_SIZE - tx_fstat);
+ i > 0; i--, c->count--, c->buf++)
st_i2c_write_tx_fifo(i2c_dev, *c->buf);
}
/**
* st_i2c_rd_fill_tx_fifo() - Fill the Tx FIFO in read mode
* @i2c_dev: Controller's private data
+ * @max: Maximum amount of data to fill into the Tx FIFO
*
* This functions fills the Tx FIFO with fixed pattern when
* in read mode to trigger clock.
*/
-static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max)
+static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, u32 max)
{
struct st_i2c_client *c = &i2c_dev->client;
u32 tx_fstat, sta;
@@ -454,12 +449,8 @@ static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max)
tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
tx_fstat &= SSC_TX_FSTAT_STATUS;
- if (max < (SSC_TXFIFO_SIZE - tx_fstat))
- i = max;
- else
- i = SSC_TXFIFO_SIZE - tx_fstat;
-
- for (; i > 0; i--, c->xfered++)
+ for (i = min(max, SSC_TXFIFO_SIZE - tx_fstat);
+ i > 0; i--, c->xfered++)
st_i2c_write_tx_fifo(i2c_dev, 0xff);
}
@@ -526,7 +517,7 @@ static void st_i2c_handle_write(struct st_i2c_dev *i2c_dev)
}
/**
- * st_i2c_handle_write() - Handle FIFO enmpty interrupt in case of read
+ * st_i2c_handle_read() - Handle FIFO empty interrupt in case of read
* @i2c_dev: Controller's private data
*/
static void st_i2c_handle_read(struct st_i2c_dev *i2c_dev)
@@ -560,7 +551,7 @@ static void st_i2c_handle_read(struct st_i2c_dev *i2c_dev)
}
/**
- * st_i2c_isr() - Interrupt routine
+ * st_i2c_isr_thread() - Interrupt routine
* @irq: interrupt number
* @data: Controller's private data
*/
@@ -649,7 +640,7 @@ static int st_i2c_xfer_msg(struct st_i2c_dev *i2c_dev, struct i2c_msg *msg,
{
struct st_i2c_client *c = &i2c_dev->client;
u32 ctl, i2c, it;
- unsigned long timeout;
+ unsigned long time_left;
int ret;
c->addr = i2c_8bit_addr_from_msg(msg);
@@ -669,7 +660,7 @@ static int st_i2c_xfer_msg(struct st_i2c_dev *i2c_dev, struct i2c_msg *msg,
i2c |= SSC_I2C_ACKG;
st_i2c_set_bits(i2c_dev->base + SSC_I2C, i2c);
- /* Write slave address */
+ /* Write target address */
st_i2c_write_tx_fifo(i2c_dev, c->addr);
/* Pre-fill Tx fifo with data in case of write */
@@ -687,15 +678,12 @@ static int st_i2c_xfer_msg(struct st_i2c_dev *i2c_dev, struct i2c_msg *msg,
st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STRTG);
}
- timeout = wait_for_completion_timeout(&i2c_dev->complete,
- i2c_dev->adap.timeout);
+ time_left = wait_for_completion_timeout(&i2c_dev->complete,
+ i2c_dev->adap.timeout);
ret = c->result;
- if (!timeout) {
- dev_err(i2c_dev->dev, "Write to slave 0x%x timed out\n",
- c->addr);
+ if (!time_left)
ret = -ETIMEDOUT;
- }
i2c = SSC_I2C_STOPG | SSC_I2C_REPSTRTG;
st_i2c_clr_bits(i2c_dev->base + SSC_I2C, i2c);
@@ -742,7 +730,6 @@ static int st_i2c_xfer(struct i2c_adapter *i2c_adap,
return (ret < 0) ? ret : i;
}
-#ifdef CONFIG_PM_SLEEP
static int st_i2c_suspend(struct device *dev)
{
struct st_i2c_dev *i2c_dev = dev_get_drvdata(dev);
@@ -764,11 +751,7 @@ static int st_i2c_resume(struct device *dev)
return 0;
}
-static SIMPLE_DEV_PM_OPS(st_i2c_pm, st_i2c_suspend, st_i2c_resume);
-#define ST_I2C_PM (&st_i2c_pm)
-#else
-#define ST_I2C_PM NULL
-#endif
+static DEFINE_SIMPLE_DEV_PM_OPS(st_i2c_pm, st_i2c_suspend, st_i2c_resume);
static u32 st_i2c_func(struct i2c_adapter *adap)
{
@@ -776,7 +759,7 @@ static u32 st_i2c_func(struct i2c_adapter *adap)
}
static const struct i2c_algorithm st_i2c_algo = {
- .master_xfer = st_i2c_xfer,
+ .xfer = st_i2c_xfer,
.functionality = st_i2c_func,
};
@@ -819,8 +802,7 @@ static int st_i2c_probe(struct platform_device *pdev)
if (!i2c_dev)
return -ENOMEM;
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
+ i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(i2c_dev->base))
return PTR_ERR(i2c_dev->base);
@@ -838,7 +820,7 @@ static int st_i2c_probe(struct platform_device *pdev)
i2c_dev->mode = I2C_MODE_STANDARD;
ret = of_property_read_u32(np, "clock-frequency", &clk_rate);
- if ((!ret) && (clk_rate == 400000))
+ if (!ret && (clk_rate == I2C_MAX_FAST_MODE_FREQ))
i2c_dev->mode = I2C_MODE_FAST;
i2c_dev->dev = &pdev->dev;
@@ -883,13 +865,11 @@ static int st_i2c_probe(struct platform_device *pdev)
return 0;
}
-static int st_i2c_remove(struct platform_device *pdev)
+static void st_i2c_remove(struct platform_device *pdev)
{
struct st_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
i2c_del_adapter(&i2c_dev->adap);
-
- return 0;
}
static const struct of_device_id st_i2c_match[] = {
@@ -903,7 +883,7 @@ static struct platform_driver st_i2c_driver = {
.driver = {
.name = "st-i2c",
.of_match_table = st_i2c_match,
- .pm = ST_I2C_PM,
+ .pm = pm_sleep_ptr(&st_i2c_pm),
},
.probe = st_i2c_probe,
.remove = st_i2c_remove,
generated by cgit (git 2.34.1) at 2025-12-25 06:46:54 +0000