[PATCH v2 1/4] Factor out _master() parts of code and identify as much as possible all related with MASTER mode

From: Luis . Oliveira
Date: Fri Oct 14 2016 - 12:54:20 EST


From: Luis Oliveira <lolivei@xxxxxxxxxxxx>

Signed-off-by: Luis Oliveira <lolivei@xxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-designware-core.c | 71 +++++++++++++++++++----------
drivers/i2c/busses/i2c-designware-platdrv.c | 37 +++++++++------
2 files changed, 71 insertions(+), 37 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 1fe93c4..cc38329 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -87,13 +87,15 @@
#define DW_IC_INTR_GEN_CALL 0x800

#define DW_IC_INTR_DEFAULT_MASK (DW_IC_INTR_RX_FULL | \
- DW_IC_INTR_TX_EMPTY | \
DW_IC_INTR_TX_ABRT | \
DW_IC_INTR_STOP_DET)
+
+#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MASK | \
+ DW_IC_INTR_TX_EMPTY)

#define DW_IC_STATUS_ACTIVITY 0x1
#define DW_IC_STATUS_TFE BIT(2)
-#define DW_IC_STATUS_MST_ACTIVITY BIT(5)
+#define DW_IC_STATUS_MASTER_ACTIVITY BIT(5)

#define DW_IC_ERR_TX_ABRT 0x1

@@ -201,6 +203,17 @@ static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
}
}

+static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
+{
+ /* Configure Tx/Rx FIFO threshold levels */
+ dw_writel(dev, dev->tx_fifo_depth / 2, DW_IC_TX_TL);
+ dw_writel(dev, 0, DW_IC_RX_TL);
+
+ /* configure the i2c master */
+ dw_writel(dev, dev->master_cfg , DW_IC_CON);
+ dw_writel(dev, DW_IC_INTR_MASTER_MASK, DW_IC_INTR_MASK);
+}
+
static u32
i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
{
@@ -317,10 +330,10 @@ static void i2c_dw_release_lock(struct dw_i2c_dev *dev)
}

/**
- * i2c_dw_init() - initialize the designware i2c master hardware
+ * i2c_dw_init() - initialize the designware i2c hardware
* @dev: device private data
*
- * This functions configures and enables the I2C master.
+ * This functions configures and enables the I2C.
* This function is called during I2C init function, and in case of timeout at
* run time.
*/
@@ -431,12 +444,9 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
"Hardware too old to adjust SDA hold time.\n");
}

- /* Configure Tx/Rx FIFO threshold levels */
- dw_writel(dev, dev->tx_fifo_depth / 2, DW_IC_TX_TL);
- dw_writel(dev, 0, DW_IC_RX_TL);
-
- /* configure the i2c master */
- dw_writel(dev, dev->master_cfg , DW_IC_CON);
+ if ((dev->master_cfg & DW_IC_CON_MASTER) &&
+ (dev->master_cfg & DW_IC_CON_SLAVE_DISABLE))
+ i2c_dw_configure_fifo_master(dev);

i2c_dw_release_lock(dev);

@@ -480,7 +490,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
*/
ic_status = dw_readl(dev, DW_IC_STATUS);
if (!dev->dynamic_tar_update_enabled ||
- (ic_status & DW_IC_STATUS_MST_ACTIVITY) ||
+ (ic_status & DW_IC_STATUS_MASTER_ACTIVITY) ||
!(ic_status & DW_IC_STATUS_TFE)) {
__i2c_dw_enable_and_wait(dev, false);
enabled = false;
@@ -520,7 +530,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)

/* Clear and enable interrupts */
dw_readl(dev, DW_IC_CLR_INTR);
- dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK);
+ dw_writel(dev, DW_IC_INTR_MASTER_MASK, DW_IC_INTR_MASK);
}

/*
@@ -540,7 +550,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
u8 *buf = dev->tx_buf;
bool need_restart = false;

- intr_mask = DW_IC_INTR_DEFAULT_MASK;
+ intr_mask = DW_IC_INTR_MASTER_MASK;

for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) {
/*
@@ -839,19 +849,13 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
* Interrupt service routine. This gets called whenever an I2C interrupt
* occurs.
*/
-static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
-{
- struct dw_i2c_dev *dev = dev_id;
- u32 stat, enabled;
-
- enabled = dw_readl(dev, DW_IC_ENABLE);
- stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
- dev_dbg(dev->dev, "%s: enabled=%#x stat=%#x\n", __func__, enabled, stat);
- if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY))
- return IRQ_NONE;

+static bool i2c_dw_irq_handler_master(struct dw_i2c_dev *dev )
+{
+ u32 stat;
+
stat = i2c_dw_read_clear_intrbits(dev);
-
+
if (stat & DW_IC_INTR_TX_ABRT) {
dev->cmd_err |= DW_IC_ERR_TX_ABRT;
dev->status = STATUS_IDLE;
@@ -895,7 +899,26 @@ tx_aborted:
i2c_dw_disable_int(dev);
dw_writel(dev, stat, DW_IC_INTR_MASK);
}
+ return true;
+}
+
+static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
+{
+ struct dw_i2c_dev *dev = dev_id;
+ u32 stat, enabled, mode;
+
+ enabled = dw_readl(dev, DW_IC_ENABLE);
+ mode = dw_readl(dev, DW_IC_CON);
+ stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
+
+ dev_dbg(dev->dev, "%s: enabled=%#x stat=%#x\n", __func__, enabled, stat);
+ if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY))
+ return IRQ_NONE;

+ if(i2c_dw_irq_handler_master(dev))
+ return IRQ_HANDLED;
+
+ complete(&dev->cmd_complete);
return IRQ_HANDLED;
}

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 0b42a12..d5986c2 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -138,6 +138,29 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
}
#endif

+static void i2c_dw_configure_master(struct platform_device *pdev)
+{
+ struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
+
+ dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
+ DW_IC_CON_RESTART_EN;
+
+ dev->functionality |= I2C_FUNC_10BIT_ADDR;
+ dev_info(&pdev->dev, "I am registed as a I2C Master!\n");
+
+ switch (dev->clk_freq) {
+ case 100000:
+ dev->master_cfg |= DW_IC_CON_SPEED_STD;
+ break;
+ case 3400000:
+ dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
+ break;
+ default:
+ dev->master_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))
@@ -222,19 +245,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK;

- dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
- DW_IC_CON_RESTART_EN;
-
- switch (dev->clk_freq) {
- case 100000:
- dev->master_cfg |= DW_IC_CON_SPEED_STD;
- break;
- case 3400000:
- dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
- break;
- default:
- dev->master_cfg |= DW_IC_CON_SPEED_FAST;
- }
+ i2c_dw_configure_master(pdev);

dev->clk = devm_clk_get(&pdev->dev, NULL);
if (!i2c_dw_plat_prepare_clk(dev, true)) {
--
2.10.1