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path: root/drivers/i2c/busses/i2c-uniphier.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-uniphier.c')
-rw-r--r--drivers/i2c/busses/i2c-uniphier.c104
1 files changed, 26 insertions, 78 deletions
diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c
index c488e558aef7..9d49a3d5d612 100644
--- a/drivers/i2c/busses/i2c-uniphier.c
+++ b/drivers/i2c/busses/i2c-uniphier.c
@@ -1,15 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
*/
#include <linux/clk.h>
@@ -26,13 +17,13 @@
#define UNIPHIER_I2C_DTRM_NACK BIT(8) /* do not return ACK */
#define UNIPHIER_I2C_DTRM_RD BIT(0) /* read transaction */
#define UNIPHIER_I2C_DREC 0x04 /* RX register */
-#define UNIPHIER_I2C_DREC_MST BIT(14) /* 1 = master, 0 = slave */
+#define UNIPHIER_I2C_DREC_MST BIT(14) /* 1 = controller, 0 = target */
#define UNIPHIER_I2C_DREC_TX BIT(13) /* 1 = transmit, 0 = receive */
#define UNIPHIER_I2C_DREC_STS BIT(12) /* stop condition detected */
#define UNIPHIER_I2C_DREC_LRB BIT(11) /* no ACK */
#define UNIPHIER_I2C_DREC_LAB BIT(9) /* arbitration lost */
#define UNIPHIER_I2C_DREC_BBN BIT(8) /* bus not busy */
-#define UNIPHIER_I2C_MYAD 0x08 /* slave address */
+#define UNIPHIER_I2C_MYAD 0x08 /* local target address */
#define UNIPHIER_I2C_CLK 0x0c /* clock frequency control */
#define UNIPHIER_I2C_BRST 0x10 /* bus reset */
#define UNIPHIER_I2C_BRST_FOEN BIT(1) /* normal operation */
@@ -44,9 +35,6 @@
#define UNIPHIER_I2C_NOISE 0x1c /* noise filter control */
#define UNIPHIER_I2C_SETUP 0x20 /* setup time control */
-#define UNIPHIER_I2C_DEFAULT_SPEED 100000
-#define UNIPHIER_I2C_MAX_SPEED 400000
-
struct uniphier_i2c_priv {
struct completion comp;
struct i2c_adapter adap;
@@ -80,18 +68,13 @@ static int uniphier_i2c_xfer_byte(struct i2c_adapter *adap, u32 txdata,
reinit_completion(&priv->comp);
txdata |= UNIPHIER_I2C_DTRM_IRQEN;
- dev_dbg(&adap->dev, "write data: 0x%04x\n", txdata);
writel(txdata, priv->membase + UNIPHIER_I2C_DTRM);
time_left = wait_for_completion_timeout(&priv->comp, adap->timeout);
- if (unlikely(!time_left)) {
- dev_err(&adap->dev, "transaction timeout\n");
+ if (unlikely(!time_left))
return -ETIMEDOUT;
- }
rxdata = readl(priv->membase + UNIPHIER_I2C_DREC);
- dev_dbg(&adap->dev, "read data: 0x%04x\n", rxdata);
-
if (rxdatap)
*rxdatap = rxdata;
@@ -107,14 +90,11 @@ static int uniphier_i2c_send_byte(struct i2c_adapter *adap, u32 txdata)
if (ret)
return ret;
- if (unlikely(rxdata & UNIPHIER_I2C_DREC_LAB)) {
- dev_dbg(&adap->dev, "arbitration lost\n");
+ if (unlikely(rxdata & UNIPHIER_I2C_DREC_LAB))
return -EAGAIN;
- }
- if (unlikely(rxdata & UNIPHIER_I2C_DREC_LRB)) {
- dev_dbg(&adap->dev, "could not get ACK\n");
+
+ if (unlikely(rxdata & UNIPHIER_I2C_DREC_LRB))
return -ENXIO;
- }
return 0;
}
@@ -124,7 +104,6 @@ static int uniphier_i2c_tx(struct i2c_adapter *adap, u16 addr, u16 len,
{
int ret;
- dev_dbg(&adap->dev, "start condition\n");
ret = uniphier_i2c_send_byte(adap, addr << 1 |
UNIPHIER_I2C_DTRM_STA |
UNIPHIER_I2C_DTRM_NACK);
@@ -146,7 +125,6 @@ static int uniphier_i2c_rx(struct i2c_adapter *adap, u16 addr, u16 len,
{
int ret;
- dev_dbg(&adap->dev, "start condition\n");
ret = uniphier_i2c_send_byte(adap, addr << 1 |
UNIPHIER_I2C_DTRM_STA |
UNIPHIER_I2C_DTRM_NACK |
@@ -170,21 +148,17 @@ static int uniphier_i2c_rx(struct i2c_adapter *adap, u16 addr, u16 len,
static int uniphier_i2c_stop(struct i2c_adapter *adap)
{
- dev_dbg(&adap->dev, "stop condition\n");
return uniphier_i2c_send_byte(adap, UNIPHIER_I2C_DTRM_STO |
UNIPHIER_I2C_DTRM_NACK);
}
-static int uniphier_i2c_master_xfer_one(struct i2c_adapter *adap,
- struct i2c_msg *msg, bool stop)
+static int uniphier_i2c_xfer_one(struct i2c_adapter *adap,
+ struct i2c_msg *msg, bool stop)
{
bool is_read = msg->flags & I2C_M_RD;
bool recovery = false;
int ret;
- dev_dbg(&adap->dev, "%s: addr=0x%02x, len=%d, stop=%d\n",
- is_read ? "receive" : "transmit", msg->addr, msg->len, stop);
-
if (is_read)
ret = uniphier_i2c_rx(adap, msg->addr, msg->len, msg->buf);
else
@@ -237,8 +211,7 @@ static int uniphier_i2c_check_bus_busy(struct i2c_adapter *adap)
return 0;
}
-static int uniphier_i2c_master_xfer(struct i2c_adapter *adap,
- struct i2c_msg *msgs, int num)
+static int uniphier_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
struct i2c_msg *msg, *emsg = msgs + num;
int ret;
@@ -251,7 +224,7 @@ static int uniphier_i2c_master_xfer(struct i2c_adapter *adap,
/* Emit STOP if it is the last message or I2C_M_STOP is set. */
bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP);
- ret = uniphier_i2c_master_xfer_one(adap, msg, stop);
+ ret = uniphier_i2c_xfer_one(adap, msg, stop);
if (ret)
return ret;
}
@@ -265,7 +238,7 @@ static u32 uniphier_i2c_functionality(struct i2c_adapter *adap)
}
static const struct i2c_algorithm uniphier_i2c_algo = {
- .master_xfer = uniphier_i2c_master_xfer,
+ .xfer = uniphier_i2c_xfer,
.functionality = uniphier_i2c_functionality,
};
@@ -335,7 +308,6 @@ static int uniphier_i2c_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct uniphier_i2c_priv *priv;
- struct resource *regs;
u32 bus_speed;
unsigned long clk_rate;
int irq, ret;
@@ -344,41 +316,27 @@ static int uniphier_i2c_probe(struct platform_device *pdev)
if (!priv)
return -ENOMEM;
- regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- priv->membase = devm_ioremap_resource(dev, regs);
+ priv->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->membase))
return PTR_ERR(priv->membase);
irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(dev, "failed to get IRQ number\n");
+ if (irq < 0)
return irq;
- }
if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed))
- bus_speed = UNIPHIER_I2C_DEFAULT_SPEED;
+ bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
- if (!bus_speed || bus_speed > UNIPHIER_I2C_MAX_SPEED) {
- dev_err(dev, "invalid clock-frequency %d\n", bus_speed);
- return -EINVAL;
- }
+ if (!bus_speed || bus_speed > I2C_MAX_FAST_MODE_FREQ)
+ return dev_err_probe(dev, -EINVAL, "invalid clock-frequency %d\n", bus_speed);
- priv->clk = devm_clk_get(dev, NULL);
- if (IS_ERR(priv->clk)) {
- dev_err(dev, "failed to get clock\n");
- return PTR_ERR(priv->clk);
- }
-
- ret = clk_prepare_enable(priv->clk);
- if (ret)
- return ret;
+ priv->clk = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(priv->clk))
+ return dev_err_probe(dev, PTR_ERR(priv->clk), "failed to enable clock\n");
clk_rate = clk_get_rate(priv->clk);
- if (!clk_rate) {
- dev_err(dev, "input clock rate should not be zero\n");
- ret = -EINVAL;
- goto disable_clk;
- }
+ if (!clk_rate)
+ return dev_err_probe(dev, -EINVAL, "input clock rate should not be zero\n");
priv->clk_cycle = clk_rate / bus_speed;
init_completion(&priv->comp);
@@ -386,7 +344,7 @@ static int uniphier_i2c_probe(struct platform_device *pdev)
priv->adap.algo = &uniphier_i2c_algo;
priv->adap.dev.parent = dev;
priv->adap.dev.of_node = dev->of_node;
- strlcpy(priv->adap.name, "UniPhier I2C", sizeof(priv->adap.name));
+ strscpy(priv->adap.name, "UniPhier I2C", sizeof(priv->adap.name));
priv->adap.bus_recovery_info = &uniphier_i2c_bus_recovery_info;
i2c_set_adapdata(&priv->adap, priv);
platform_set_drvdata(pdev, priv);
@@ -395,27 +353,17 @@ static int uniphier_i2c_probe(struct platform_device *pdev)
ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name,
priv);
- if (ret) {
- dev_err(dev, "failed to request irq %d\n", irq);
- goto disable_clk;
- }
-
- ret = i2c_add_adapter(&priv->adap);
-disable_clk:
if (ret)
- clk_disable_unprepare(priv->clk);
+ return dev_err_probe(dev, ret, "failed to request irq %d\n", irq);
- return ret;
+ return i2c_add_adapter(&priv->adap);
}
-static int uniphier_i2c_remove(struct platform_device *pdev)
+static void uniphier_i2c_remove(struct platform_device *pdev)
{
struct uniphier_i2c_priv *priv = platform_get_drvdata(pdev);
i2c_del_adapter(&priv->adap);
- clk_disable_unprepare(priv->clk);
-
- return 0;
}
static int __maybe_unused uniphier_i2c_suspend(struct device *dev)
generated by cgit (git 2.34.1) at 2025-12-25 05:43:07 +0000