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Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c136
1 files changed, 93 insertions, 43 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index ebaa78d17d6e..9fcb13beeb8f 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -54,20 +54,15 @@
#define I2C_INT_STATUS 0x068
#define I2C_INT_BUS_CLR_DONE BIT(11)
#define I2C_INT_PACKET_XFER_COMPLETE BIT(7)
-#define I2C_INT_ALL_PACKETS_XFER_COMPLETE BIT(6)
-#define I2C_INT_TX_FIFO_OVERFLOW BIT(5)
-#define I2C_INT_RX_FIFO_UNDERFLOW BIT(4)
#define I2C_INT_NO_ACK BIT(3)
#define I2C_INT_ARBITRATION_LOST BIT(2)
#define I2C_INT_TX_FIFO_DATA_REQ BIT(1)
#define I2C_INT_RX_FIFO_DATA_REQ BIT(0)
#define I2C_CLK_DIVISOR 0x06c
#define I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT 16
-#define I2C_CLK_MULTIPLIER_STD_FAST_MODE 8
#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_REG3_SW_PROG BIT(26)
#define DVC_CTRL_REG3_I2C_DONE_INTR_EN BIT(30)
@@ -75,24 +70,22 @@
#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_NO_ACK BIT(0)
+#define I2C_ERR_ARBITRATION_LOST BIT(1)
+#define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
+#define I2C_ERR_RX_BUFFER_OVERFLOW BIT(3)
#define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
#define PACKET_HEADER0_PACKET_ID_SHIFT 16
#define PACKET_HEADER0_CONT_ID_SHIFT 12
#define PACKET_HEADER0_PROTOCOL_I2C BIT(4)
-#define I2C_HEADER_HIGHSPEED_MODE BIT(22)
#define I2C_HEADER_CONT_ON_NAK BIT(21)
-#define I2C_HEADER_SEND_START_BYTE BIT(20)
#define I2C_HEADER_READ BIT(19)
#define I2C_HEADER_10BIT_ADDR BIT(18)
#define I2C_HEADER_IE_ENABLE BIT(17)
#define I2C_HEADER_REPEAT_START BIT(16)
#define I2C_HEADER_CONTINUE_XFER BIT(15)
-#define I2C_HEADER_MASTER_ADDR_SHIFT 12
#define I2C_HEADER_SLAVE_ADDR_SHIFT 1
#define I2C_BUS_CLEAR_CNFG 0x084
@@ -106,8 +99,6 @@
#define I2C_CONFIG_LOAD 0x08C
#define I2C_MSTR_CONFIG_LOAD BIT(0)
-#define I2C_SLV_CONFIG_LOAD BIT(1)
-#define I2C_TIMEOUT_CONFIG_LOAD BIT(2)
#define I2C_CLKEN_OVERRIDE 0x090
#define I2C_MST_CORE_CLKEN_OVR BIT(0)
@@ -133,7 +124,6 @@
#define I2C_STANDARD_MODE 100000
#define I2C_FAST_MODE 400000
#define I2C_FAST_PLUS_MODE 1000000
-#define I2C_HS_MODE 3500000
/* Packet header size in bytes */
#define I2C_PACKET_HEADER_SIZE 12
@@ -280,6 +270,7 @@ 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 +297,7 @@ 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 +305,7 @@ 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 +320,13 @@ 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 +477,7 @@ 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;
}
@@ -499,6 +490,13 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
size_t buf_remaining = i2c_dev->msg_buf_remaining;
int words_to_transfer;
+ /*
+ * Catch overflow due to message fully sent
+ * before the check for RX FIFO availability.
+ */
+ if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining)))
+ return -EINVAL;
+
if (i2c_dev->hw->has_mst_fifo) {
val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS);
rx_fifo_avail = (val & I2C_MST_FIFO_STATUS_RX_MASK) >>
@@ -525,7 +523,11 @@ 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);
+ /*
+ * buf_remaining > 3 check not needed as rx_fifo_avail == 0
+ * when (words_to_transfer was > rx_fifo_avail) earlier
+ * in this function.
+ */
val = i2c_readl(i2c_dev, I2C_RX_FIFO);
val = cpu_to_le32(val);
memcpy(buf, &val, buf_remaining);
@@ -533,7 +535,10 @@ 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);
+ /* RX FIFO must be drained, otherwise it's an Overflow case. */
+ if (WARN_ON_ONCE(rx_fifo_avail))
+ return -EINVAL;
+
i2c_dev->msg_buf_remaining = buf_remaining;
i2c_dev->msg_buf = buf;
@@ -591,7 +596,11 @@ 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);
+ /*
+ * buf_remaining > 3 check not needed as tx_fifo_avail == 0
+ * when (words_to_transfer was > tx_fifo_avail) earlier
+ * in this function for non-zero words_to_transfer.
+ */
memcpy(&val, buf, buf_remaining);
val = le32_to_cpu(val);
@@ -680,10 +689,11 @@ 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,
@@ -700,7 +710,7 @@ static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev, bool clk_reinit)
u32 val;
int err;
u32 clk_divisor, clk_multiplier;
- u32 tsu_thd = 0;
+ u32 tsu_thd;
u8 tlow, thigh;
err = pm_runtime_get_sync(i2c_dev->dev);
@@ -856,10 +866,15 @@ 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)
- tegra_i2c_empty_rx_fifo(i2c_dev);
- else
- BUG();
+ if (tegra_i2c_empty_rx_fifo(i2c_dev)) {
+ /*
+ * Overflow error condition: message fully sent,
+ * with no XFER_COMPLETE interrupt but hardware
+ * asks to transfer more.
+ */
+ i2c_dev->msg_err |= I2C_ERR_RX_BUFFER_OVERFLOW;
+ goto err;
+ }
}
if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
@@ -885,7 +900,14 @@ 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);
+ /*
+ * Underflow error condition: XFER_COMPLETE before message
+ * fully sent.
+ */
+ if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) {
+ i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
+ goto err;
+ }
complete(&i2c_dev->msg_complete);
}
goto done;
@@ -1024,7 +1046,8 @@ 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 +1184,8 @@ unlock:
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 ?
@@ -1225,11 +1247,11 @@ unlock:
}
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;
- int ret = 0;
+ int ret;
ret = pm_runtime_get_sync(i2c_dev->dev);
if (ret < 0) {
@@ -1271,14 +1293,15 @@ static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
{
struct device_node *np = i2c_dev->dev->of_node;
int ret;
+ bool multi_mode;
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_mode = of_property_read_bool(np, "multi-master");
+ i2c_dev->is_multimaster_mode = multi_mode;
}
static const struct i2c_algorithm tegra_i2c_algo = {
@@ -1500,7 +1523,7 @@ static int tegra_i2c_probe(struct platform_device *pdev)
void __iomem *base;
phys_addr_t base_phys;
int irq;
- int ret = 0;
+ int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base_phys = res->start;
@@ -1517,7 +1540,9 @@ static int tegra_i2c_probe(struct platform_device *pdev)
div_clk = devm_clk_get(&pdev->dev, "div-clk");
if (IS_ERR(div_clk)) {
- dev_err(&pdev->dev, "missing controller clock\n");
+ if (PTR_ERR(div_clk) != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "missing controller clock\n");
+
return PTR_ERR(div_clk);
}
@@ -1622,7 +1647,7 @@ 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;
@@ -1687,10 +1712,35 @@ static int tegra_i2c_remove(struct platform_device *pdev)
}
#ifdef CONFIG_PM_SLEEP
+static int tegra_i2c_suspend(struct device *dev)
+{
+ struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+
+ i2c_mark_adapter_suspended(&i2c_dev->adapter);
+
+ return 0;
+}
+
+static int tegra_i2c_resume(struct device *dev)
+{
+ struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
+ int err;
+
+ err = tegra_i2c_init(i2c_dev, false);
+ if (err)
+ return err;
+
+ i2c_mark_adapter_resumed(&i2c_dev->adapter);
+
+ return 0;
+}
+
static const struct dev_pm_ops tegra_i2c_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume)
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
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