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authorDave Airlie <airlied@redhat.com>2015-04-20 11:32:26 +1000
committerDave Airlie <airlied@redhat.com>2015-04-20 13:05:20 +1000
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /drivers/i2c/busses/i2c-davinci.c
parentmedia-bus: Fixup RGB444_1X12, RGB565_1X16, and YUV8_1X24 media bus format (diff)
parentMerge branch 'turbostat' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux (diff)
downloadlinux-dev-2c33ce009ca2389dbf0535d0672214d09738e35e.tar.xz
linux-dev-2c33ce009ca2389dbf0535d0672214d09738e35e.zip
Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/i2c/busses/i2c-davinci.c')
-rw-r--r--drivers/i2c/busses/i2c-davinci.c194
1 files changed, 143 insertions, 51 deletions
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 6dc7ff5d3d9a..4788a32afb86 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -60,6 +60,12 @@
#define DAVINCI_I2C_IVR_REG 0x28
#define DAVINCI_I2C_EMDR_REG 0x2c
#define DAVINCI_I2C_PSC_REG 0x30
+#define DAVINCI_I2C_FUNC_REG 0x48
+#define DAVINCI_I2C_DIR_REG 0x4c
+#define DAVINCI_I2C_DIN_REG 0x50
+#define DAVINCI_I2C_DOUT_REG 0x54
+#define DAVINCI_I2C_DSET_REG 0x58
+#define DAVINCI_I2C_DCLR_REG 0x5c
#define DAVINCI_I2C_IVR_AAS 0x07
#define DAVINCI_I2C_IVR_SCD 0x06
@@ -93,6 +99,29 @@
#define DAVINCI_I2C_IMR_NACK BIT(1)
#define DAVINCI_I2C_IMR_AL BIT(0)
+/* set SDA and SCL as GPIO */
+#define DAVINCI_I2C_FUNC_PFUNC0 BIT(0)
+
+/* set SCL as output when used as GPIO*/
+#define DAVINCI_I2C_DIR_PDIR0 BIT(0)
+/* set SDA as output when used as GPIO*/
+#define DAVINCI_I2C_DIR_PDIR1 BIT(1)
+
+/* read SCL GPIO level */
+#define DAVINCI_I2C_DIN_PDIN0 BIT(0)
+/* read SDA GPIO level */
+#define DAVINCI_I2C_DIN_PDIN1 BIT(1)
+
+/*set the SCL GPIO high */
+#define DAVINCI_I2C_DSET_PDSET0 BIT(0)
+/*set the SDA GPIO high */
+#define DAVINCI_I2C_DSET_PDSET1 BIT(1)
+
+/* set the SCL GPIO low */
+#define DAVINCI_I2C_DCLR_PDCLR0 BIT(0)
+/* set the SDA GPIO low */
+#define DAVINCI_I2C_DCLR_PDCLR1 BIT(1)
+
struct davinci_i2c_dev {
struct device *dev;
void __iomem *base;
@@ -129,43 +158,6 @@ static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
return readw_relaxed(i2c_dev->base + reg);
}
-/* Generate a pulse on the i2c clock pin. */
-static void davinci_i2c_clock_pulse(unsigned int scl_pin)
-{
- u16 i;
-
- if (scl_pin) {
- /* Send high and low on the SCL line */
- for (i = 0; i < 9; i++) {
- gpio_set_value(scl_pin, 0);
- udelay(20);
- gpio_set_value(scl_pin, 1);
- udelay(20);
- }
- }
-}
-
-/* This routine does i2c bus recovery as specified in the
- * i2c protocol Rev. 03 section 3.16 titled "Bus clear"
- */
-static void davinci_i2c_recover_bus(struct davinci_i2c_dev *dev)
-{
- u32 flag = 0;
- struct davinci_i2c_platform_data *pdata = dev->pdata;
-
- dev_err(dev->dev, "initiating i2c bus recovery\n");
- /* Send NACK to the slave */
- flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
- flag |= DAVINCI_I2C_MDR_NACK;
- /* write the data into mode register */
- davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
- davinci_i2c_clock_pulse(pdata->scl_pin);
- /* Send STOP */
- flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG);
- flag |= DAVINCI_I2C_MDR_STP;
- davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
-}
-
static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev,
int val)
{
@@ -263,6 +255,99 @@ static int i2c_davinci_init(struct davinci_i2c_dev *dev)
}
/*
+ * This routine does i2c bus recovery by using i2c_generic_gpio_recovery
+ * which is provided by I2C Bus recovery infrastructure.
+ */
+static void davinci_i2c_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ /* Disable interrupts */
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, 0);
+
+ /* put I2C into reset */
+ davinci_i2c_reset_ctrl(dev, 0);
+}
+
+static void davinci_i2c_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ i2c_davinci_init(dev);
+}
+
+static struct i2c_bus_recovery_info davinci_i2c_gpio_recovery_info = {
+ .recover_bus = i2c_generic_gpio_recovery,
+ .prepare_recovery = davinci_i2c_prepare_recovery,
+ .unprepare_recovery = davinci_i2c_unprepare_recovery,
+};
+
+static void davinci_i2c_set_scl(struct i2c_adapter *adap, int val)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ if (val)
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_DSET_REG,
+ DAVINCI_I2C_DSET_PDSET0);
+ else
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_DCLR_REG,
+ DAVINCI_I2C_DCLR_PDCLR0);
+}
+
+static int davinci_i2c_get_scl(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+ int val;
+
+ /* read the state of SCL */
+ val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG);
+ return val & DAVINCI_I2C_DIN_PDIN0;
+}
+
+static int davinci_i2c_get_sda(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+ int val;
+
+ /* read the state of SDA */
+ val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG);
+ return val & DAVINCI_I2C_DIN_PDIN1;
+}
+
+static void davinci_i2c_scl_prepare_recovery(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ davinci_i2c_prepare_recovery(adap);
+
+ /* SCL output, SDA input */
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_DIR_REG, DAVINCI_I2C_DIR_PDIR0);
+
+ /* change to GPIO mode */
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG,
+ DAVINCI_I2C_FUNC_PFUNC0);
+}
+
+static void davinci_i2c_scl_unprepare_recovery(struct i2c_adapter *adap)
+{
+ struct davinci_i2c_dev *dev = i2c_get_adapdata(adap);
+
+ /* change back to I2C mode */
+ davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, 0);
+
+ davinci_i2c_unprepare_recovery(adap);
+}
+
+static struct i2c_bus_recovery_info davinci_i2c_scl_recovery_info = {
+ .recover_bus = i2c_generic_scl_recovery,
+ .set_scl = davinci_i2c_set_scl,
+ .get_scl = davinci_i2c_get_scl,
+ .get_sda = davinci_i2c_get_sda,
+ .prepare_recovery = davinci_i2c_scl_prepare_recovery,
+ .unprepare_recovery = davinci_i2c_scl_unprepare_recovery,
+};
+
+/*
* Waiting for bus not busy
*/
static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
@@ -282,8 +367,7 @@ static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev,
return -ETIMEDOUT;
} else {
to_cnt = 0;
- davinci_i2c_recover_bus(dev);
- i2c_davinci_init(dev);
+ i2c_recover_bus(&dev->adapter);
}
}
if (allow_sleep)
@@ -304,7 +388,7 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
struct davinci_i2c_platform_data *pdata = dev->pdata;
u32 flag;
u16 w;
- int r;
+ unsigned long time_left;
/* Introduce a delay, required for some boards (e.g Davinci EVM) */
if (pdata->bus_delay)
@@ -368,11 +452,11 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
flag |= DAVINCI_I2C_MDR_STP;
davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
- r = wait_for_completion_timeout(&dev->cmd_complete, dev->adapter.timeout);
- if (r == 0) {
+ time_left = wait_for_completion_timeout(&dev->cmd_complete,
+ dev->adapter.timeout);
+ if (!time_left) {
dev_err(dev->dev, "controller timed out\n");
- davinci_i2c_recover_bus(dev);
- i2c_davinci_init(dev);
+ i2c_recover_bus(adap);
dev->buf_len = 0;
return -ETIMEDOUT;
}
@@ -380,17 +464,13 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
/* This should be 0 if all bytes were transferred
* or dev->cmd_err denotes an error.
*/
- if (r >= 0) {
- dev_err(dev->dev, "abnormal termination buf_len=%i\n",
- dev->buf_len);
- r = -EREMOTEIO;
- }
+ dev_err(dev->dev, "abnormal termination buf_len=%i\n",
+ dev->buf_len);
dev->terminate = 1;
wmb();
dev->buf_len = 0;
+ return -EREMOTEIO;
}
- if (r < 0)
- return r;
/* no error */
if (likely(!dev->cmd_err))
@@ -674,6 +754,10 @@ static int davinci_i2c_probe(struct platform_device *pdev)
if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency",
&prop))
dev->pdata->bus_freq = prop / 1000;
+
+ dev->pdata->has_pfunc =
+ of_property_read_bool(pdev->dev.of_node,
+ "ti,has-pfunc");
} else if (!dev->pdata) {
dev->pdata = &davinci_i2c_platform_data_default;
}
@@ -715,6 +799,14 @@ static int davinci_i2c_probe(struct platform_device *pdev)
adap->timeout = DAVINCI_I2C_TIMEOUT;
adap->dev.of_node = pdev->dev.of_node;
+ if (dev->pdata->has_pfunc)
+ adap->bus_recovery_info = &davinci_i2c_scl_recovery_info;
+ else if (dev->pdata->scl_pin) {
+ adap->bus_recovery_info = &davinci_i2c_gpio_recovery_info;
+ adap->bus_recovery_info->scl_gpio = dev->pdata->scl_pin;
+ adap->bus_recovery_info->sda_gpio = dev->pdata->sda_pin;
+ }
+
adap->nr = pdev->id;
r = i2c_add_numbered_adapter(adap);
if (r) {