Commit 28683e84 authored by Jerome Brunet's avatar Jerome Brunet Committed by Wolfram Sang

i2c: meson: fix clock setting overwrite

When the slave address is written in do_start(), SLAVE_ADDR is written
completely. This may overwrite some setting related to the clock rate
or signal filtering.

Fix this by writing only the bits related to slave address. To avoid
causing unexpected changed, explicitly disable filtering or high/low
clock mode which may have been left over by the bootloader.

Fixes: 30021e37 ("i2c: add support for Amlogic Meson I2C controller")
Signed-off-by: default avatarJerome Brunet <jbrunet@baylibre.com>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent fa4d3055
...@@ -5,6 +5,7 @@ ...@@ -5,6 +5,7 @@
* Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
*/ */
#include <linux/bitfield.h>
#include <linux/clk.h> #include <linux/clk.h>
#include <linux/completion.h> #include <linux/completion.h>
#include <linux/i2c.h> #include <linux/i2c.h>
...@@ -38,6 +39,12 @@ ...@@ -38,6 +39,12 @@
#define REG_CTRL_CLKDIVEXT_SHIFT 28 #define REG_CTRL_CLKDIVEXT_SHIFT 28
#define REG_CTRL_CLKDIVEXT_MASK GENMASK(29, 28) #define REG_CTRL_CLKDIVEXT_MASK GENMASK(29, 28)
#define REG_SLV_ADDR GENMASK(7, 0)
#define REG_SLV_SDA_FILTER GENMASK(10, 8)
#define REG_SLV_SCL_FILTER GENMASK(13, 11)
#define REG_SLV_SCL_LOW GENMASK(27, 16)
#define REG_SLV_SCL_LOW_EN BIT(28)
#define I2C_TIMEOUT_MS 500 #define I2C_TIMEOUT_MS 500
enum { enum {
...@@ -147,6 +154,9 @@ static void meson_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq) ...@@ -147,6 +154,9 @@ static void meson_i2c_set_clk_div(struct meson_i2c *i2c, unsigned int freq)
meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIVEXT_MASK, meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_CLKDIVEXT_MASK,
(div >> 10) << REG_CTRL_CLKDIVEXT_SHIFT); (div >> 10) << REG_CTRL_CLKDIVEXT_SHIFT);
/* Disable HIGH/LOW mode */
meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_SCL_LOW_EN, 0);
dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__, dev_dbg(i2c->dev, "%s: clk %lu, freq %u, div %u\n", __func__,
clk_rate, freq, div); clk_rate, freq, div);
} }
...@@ -280,7 +290,10 @@ static void meson_i2c_do_start(struct meson_i2c *i2c, struct i2c_msg *msg) ...@@ -280,7 +290,10 @@ static void meson_i2c_do_start(struct meson_i2c *i2c, struct i2c_msg *msg)
token = (msg->flags & I2C_M_RD) ? TOKEN_SLAVE_ADDR_READ : token = (msg->flags & I2C_M_RD) ? TOKEN_SLAVE_ADDR_READ :
TOKEN_SLAVE_ADDR_WRITE; TOKEN_SLAVE_ADDR_WRITE;
writel(msg->addr << 1, i2c->regs + REG_SLAVE_ADDR);
meson_i2c_set_mask(i2c, REG_SLAVE_ADDR, REG_SLV_ADDR,
FIELD_PREP(REG_SLV_ADDR, msg->addr << 1));
meson_i2c_add_token(i2c, TOKEN_START); meson_i2c_add_token(i2c, TOKEN_START);
meson_i2c_add_token(i2c, token); meson_i2c_add_token(i2c, token);
} }
...@@ -461,6 +474,10 @@ static int meson_i2c_probe(struct platform_device *pdev) ...@@ -461,6 +474,10 @@ static int meson_i2c_probe(struct platform_device *pdev)
return ret; return ret;
} }
/* Disable filtering */
meson_i2c_set_mask(i2c, REG_SLAVE_ADDR,
REG_SLV_SDA_FILTER | REG_SLV_SCL_FILTER, 0);
meson_i2c_set_clk_div(i2c, timings.bus_freq_hz); meson_i2c_set_clk_div(i2c, timings.bus_freq_hz);
return 0; return 0;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment