Fix checkpatch.pl warning(s)/error(s)/check(s) in i2c-tegra.c

Ignore checkpatch WARNING for 80 character line limit at
places where renaming fields compromises readability.

Delay of approximately 1msec in flush i2c FIFO polling loop
achieved by usleep_range call as msleep can take 20msecs.

Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
as needed. Replace BUG() with error handling code.
Define I2C_ERR_UNEXPECTED_STATUS for error handling.

Signed-off-by: Bitan Biswas <bbis...@nvidia.com>
---
 drivers/i2c/busses/i2c-tegra.c | 61 ++++++++++++++++++++++--------------------
 1 file changed, 32 insertions(+), 29 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 1dbba39..161eb28 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -67,17 +67,18 @@
 
 #define DVC_CTRL_REG1                          0x000
 #define DVC_CTRL_REG1_INTR_EN                  BIT(10)
-#define DVC_CTRL_REG2                          0x004
-#define DVC_CTRL_REG3                          0x008
+#define DVC_CTRL_REG2                          BIT(2)
+#define DVC_CTRL_REG3                          BIT(3)
 #define DVC_CTRL_REG3_SW_PROG                  BIT(26)
 #define DVC_CTRL_REG3_I2C_DONE_INTR_EN         BIT(30)
 #define DVC_STATUS                             0x00c
 #define DVC_STATUS_I2C_DONE_INTR               BIT(30)
 
-#define I2C_ERR_NONE                           0x00
-#define I2C_ERR_NO_ACK                         0x01
-#define I2C_ERR_ARBITRATION_LOST               0x02
-#define I2C_ERR_UNKNOWN_INTERRUPT              0x04
+#define I2C_ERR_NONE                           0x0
+#define I2C_ERR_NO_ACK                         BIT(0)
+#define I2C_ERR_ARBITRATION_LOST               BIT(1)
+#define I2C_ERR_UNKNOWN_INTERRUPT              BIT(2)
+#define I2C_ERR_UNEXPECTED_STATUS              BIT(3)
 
 #define PACKET_HEADER0_HEADER_SIZE_SHIFT       28
 #define PACKET_HEADER0_PACKET_ID_SHIFT         16
@@ -280,6 +281,7 @@ struct tegra_i2c_dev {
        u32 bus_clk_rate;
        u16 clk_divisor_non_hs_mode;
        bool is_multimaster_mode;
+       /* xfer_lock: lock to serialize transfer submission and processing */
        spinlock_t xfer_lock;
        struct dma_chan *tx_dma_chan;
        struct dma_chan *rx_dma_chan;
@@ -306,7 +308,7 @@ static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, 
unsigned long reg)
  * to the I2C block inside the DVC block
  */
 static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
-       unsigned long reg)
+                                       unsigned long reg)
 {
        if (i2c_dev->is_dvc)
                reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40;
@@ -314,7 +316,7 @@ static unsigned long tegra_i2c_reg_addr(struct 
tegra_i2c_dev *i2c_dev,
 }
 
 static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
-       unsigned long reg)
+                      unsigned long reg)
 {
        writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
 
@@ -329,13 +331,13 @@ static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, 
unsigned long reg)
 }
 
 static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
-       unsigned long reg, int len)
+                       unsigned long reg, int len)
 {
        writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
 }
 
 static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data,
-       unsigned long reg, int len)
+                      unsigned long reg, int len)
 {
        readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
 }
@@ -486,7 +488,7 @@ static int tegra_i2c_flush_fifos(struct tegra_i2c_dev 
*i2c_dev)
                        dev_warn(i2c_dev->dev, "timeout waiting for fifo 
flush\n");
                        return -ETIMEDOUT;
                }
-               msleep(1);
+               usleep_range(1000, 2000);
        }
        return 0;
 }
@@ -525,7 +527,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev 
*i2c_dev)
         * prevent overwriting past the end of buf
         */
        if (rx_fifo_avail > 0 && buf_remaining > 0) {
-               BUG_ON(buf_remaining > 3);
                val = i2c_readl(i2c_dev, I2C_RX_FIFO);
                val = cpu_to_le32(val);
                memcpy(buf, &val, buf_remaining);
@@ -533,7 +534,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev 
*i2c_dev)
                rx_fifo_avail--;
        }
 
-       BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
        i2c_dev->msg_buf_remaining = buf_remaining;
        i2c_dev->msg_buf = buf;
 
@@ -591,7 +591,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev 
*i2c_dev)
         * boundary and fault.
         */
        if (tx_fifo_avail > 0 && buf_remaining > 0) {
-               BUG_ON(buf_remaining > 3);
                memcpy(&val, buf, buf_remaining);
                val = le32_to_cpu(val);
 
@@ -680,10 +679,11 @@ static int tegra_i2c_wait_for_config_load(struct 
tegra_i2c_dev *i2c_dev)
                i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);
                if (in_interrupt())
                        err = readl_poll_timeout_atomic(addr, val, val == 0,
-                                       1000, I2C_CONFIG_LOAD_TIMEOUT);
+                                                       1000,
+                                                       
I2C_CONFIG_LOAD_TIMEOUT);
                else
-                       err = readl_poll_timeout(addr, val, val == 0,
-                                       1000, I2C_CONFIG_LOAD_TIMEOUT);
+                       err = readl_poll_timeout(addr, val, val == 0, 1000,
+                                                I2C_CONFIG_LOAD_TIMEOUT);
 
                if (err) {
                        dev_warn(i2c_dev->dev,
@@ -856,10 +856,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 
        if (!i2c_dev->is_curr_dma_xfer) {
                if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
-                       if (i2c_dev->msg_buf_remaining)
+                       if (i2c_dev->msg_buf_remaining) {
                                tegra_i2c_empty_rx_fifo(i2c_dev);
-                       else
-                               BUG();
+                       } else {
+                               dev_err(i2c_dev->dev, "unexpected rx data 
request\n");
+                               i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
+                               goto err;
+                       }
                }
 
                if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
@@ -885,7 +888,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
        if (status & I2C_INT_PACKET_XFER_COMPLETE) {
                if (i2c_dev->is_curr_dma_xfer)
                        i2c_dev->msg_buf_remaining = 0;
-               BUG_ON(i2c_dev->msg_buf_remaining);
+               WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
                complete(&i2c_dev->msg_complete);
        }
        goto done;
@@ -1024,7 +1027,7 @@ static int tegra_i2c_issue_bus_clear(struct i2c_adapter 
*adap)
 }
 
 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
-       struct i2c_msg *msg, enum msg_end_type end_state)
+                             struct i2c_msg *msg, enum msg_end_type end_state)
 {
        u32 packet_header;
        u32 int_mask;
@@ -1161,9 +1164,8 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev 
*i2c_dev,
                if (err)
                        return err;
 
-               time_left = wait_for_completion_timeout(
-                                               &i2c_dev->dma_complete,
-                                               msecs_to_jiffies(xfer_time));
+               time_left = wait_for_completion_timeout(&i2c_dev->dma_complete,
+                                                       
msecs_to_jiffies(xfer_time));
                if (time_left == 0) {
                        dev_err(i2c_dev->dev, "DMA transfer timeout\n");
                        dmaengine_terminate_sync(i2c_dev->msg_read ?
@@ -1225,7 +1227,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev 
*i2c_dev,
 }
 
 static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
-       int num)
+                         int num)
 {
        struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
        int i;
@@ -1273,12 +1275,12 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev 
*i2c_dev)
        int ret;
 
        ret = of_property_read_u32(np, "clock-frequency",
-                       &i2c_dev->bus_clk_rate);
+                                  &i2c_dev->bus_clk_rate);
        if (ret)
                i2c_dev->bus_clk_rate = 100000; /* default clock rate */
 
        i2c_dev->is_multimaster_mode = of_property_read_bool(np,
-                       "multi-master");
+                                                            "multi-master");
 }
 
 static const struct i2c_algorithm tegra_i2c_algo = {
@@ -1622,7 +1624,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
        }
 
        ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
-                       tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
+                              tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
        if (ret) {
                dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
                goto release_dma;
@@ -1715,6 +1717,7 @@ static const struct dev_pm_ops tegra_i2c_pm = {
        SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume,
                           NULL)
 };
+
 #define TEGRA_I2C_PM   (&tegra_i2c_pm)
 #else
 #define TEGRA_I2C_PM   NULL
-- 
2.7.4

Reply via email to