[PATCH v7 6/6] i2c: designware: enable SLAVE in platform module

From: Luis Oliveira
Date: Mon Mar 20 2017 - 07:24:13 EST


- Slave mode selected in platform module if the support is detected in
the DT.

Signed-off-by: Luis Oliveira <lolivei@xxxxxxxxxxxx>
---
v6-v7
- no changes

drivers/i2c/busses/Kconfig | 1 +
drivers/i2c/busses/i2c-designware-platdrv.c | 41 +++++++++++++++++++++++++----
2 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index f23575da67fd..d55b0fbff5fb 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -484,6 +484,7 @@ config I2C_DESIGNWARE_SLAVE
select I2C_SLAVE
select I2C_SLAVE_EEPROM
depends on I2C_DESIGNWARE_PLATFORM
+ default y
help
If you say yes to this option, support will be included for the
Synopsys DesignWare I2C slave adapter.
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 7f689df9aa7a..939039b4c41b 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -1,5 +1,5 @@
/*
- * Synopsys DesignWare I2C adapter driver (master only).
+ * Synopsys DesignWare I2C adapter driver.
*
* Based on the TI DAVINCI I2C adapter driver.
*
@@ -142,9 +142,13 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev)

static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
{
+ dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
+
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
DW_IC_CON_RESTART_EN;

+ dev->mode = DW_IC_MASTER;
+
switch (dev->clk_freq) {
case 100000:
dev->master_cfg |= DW_IC_CON_SPEED_STD;
@@ -157,6 +161,28 @@ static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
}
}

+static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
+{
+ dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
+
+ dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
+ DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED |
+ DW_IC_CON_SPEED_FAST;
+
+ dev->mode = DW_IC_SLAVE;
+
+ switch (dev->clk_freq) {
+ case 100000:
+ dev->slave_cfg |= DW_IC_CON_SPEED_STD;
+ break;
+ case 3400000:
+ dev->slave_cfg |= DW_IC_CON_SPEED_HIGH;
+ break;
+ default:
+ dev->slave_cfg |= DW_IC_CON_SPEED_FAST;
+ }
+}
+
static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare)
{
if (IS_ERR(i_dev->clk))
@@ -270,9 +296,10 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
if (ret)
goto exit_reset;

- dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
-
- i2c_dw_configure_master(dev);
+ if (i2c_detect_slave_mode(&pdev->dev))
+ i2c_dw_configure_slave(dev);
+ else
+ i2c_dw_configure_master(dev);

dev->clk = devm_clk_get(&pdev->dev, NULL);
if (!i2c_dw_plat_prepare_clk(dev, true)) {
@@ -301,7 +328,11 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
pm_runtime_enable(&pdev->dev);
}

- ret = i2c_dw_probe(dev);
+ if (dev->mode == DW_IC_SLAVE)
+ ret = i2c_dw_probe_slave(dev);
+ else
+ ret = i2c_dw_probe(dev);
+
if (ret)
goto exit_probe;

--
2.11.0