[PATCH v5 2/7] i2c: designware: refactoring of the i2c-designware
From: Luis Oliveira
Date: Wed Dec 28 2016 - 09:48:19 EST
- Factor out all _master() part of code from i2c-designware-core
and i2c-designware-platdrv to separate functions.
- Standardize all code related with MASTER mode.
- I have to take off DW_IC_INTR_TX_EMPTY from DW_IC_INTR_DEFAULT_MASK
because it is master specific.
The purpose of this is to prepare the controller to have is I2C MASTER
flow in a separate driver. To do this first all the
functions/definitions related to the MASTER flow were identified.
Signed-off-by: Luis Oliveira <lolivei@xxxxxxxxxxxx>
---
Changes V4->V5: (ACK by Andy)
Fixed the bellow issues:
- Removed a part belonging to slave patch
- Removed unused variable "mode"
- Changed dev_info() to dev_dbg()
drivers/i2c/busses/i2c-designware-core.c | 56 ++++++++++++++++++-----------
drivers/i2c/busses/i2c-designware-platdrv.c | 35 +++++++++++-------
2 files changed, 58 insertions(+), 33 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 9d724a6a7ec8..951ababbd9a3 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -87,10 +87,12 @@
#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_SDA_HOLD_RX_SHIFT 16
@@ -202,6 +204,16 @@ 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);
+}
+
static u32
i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset)
{
@@ -318,10 +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.
*/
@@ -440,12 +452,7 @@ 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);
+ i2c_dw_configure_fifo_master(dev);
i2c_dw_release_lock(dev);
@@ -513,7 +520,7 @@ 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);
}
/*
@@ -533,7 +540,7 @@ 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++) {
u32 flags = msgs[dev->msg_write_idx].flags;
@@ -886,16 +893,9 @@ 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)
+int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
{
- 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;
+ u32 stat;
stat = i2c_dw_read_clear_intrbits(dev);
@@ -932,6 +932,22 @@ static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
i2c_dw_disable_int(dev);
dw_writel(dev, stat, DW_IC_INTR_MASK);
}
+ return 0;
+}
+
+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;
+
+ i2c_dw_irq_handler_master(dev);
return IRQ_HANDLED;
}
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 4070baea4fb9..5cf4df63dbe8 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -139,6 +139,27 @@ 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_dbg(&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))
@@ -245,19 +266,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
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;
-
- 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)) {
--
2.11.0