From 89a1e1bd7ba9a6711908bb79af0af6cbdf4a7e79 Mon Sep 17 00:00:00 2001 From: Luis Oliveira Date: Wed, 14 Jun 2017 11:43:22 +0100 Subject: [PATCH] i2c: designware: refactoring of the i2c-designware - 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 Acked-by: Andy Shevchenko Acked-by: Jarkko Nikula Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-designware-core.c | 56 +++++++++++++++++------------ drivers/i2c/busses/i2c-designware-platdrv.c | 31 +++++++++------- 2 files changed, 52 insertions(+), 35 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c index d9cab6d..e8a7621 100644 --- a/drivers/i2c/busses/i2c-designware-core.c +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -87,10 +87,10 @@ #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 +202,16 @@ 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) { @@ -440,13 +450,7 @@ 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); return 0; @@ -511,7 +515,7 @@ 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); } /* @@ -531,7 +535,7 @@ 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; @@ -881,22 +885,14 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) } /* - * Interrupt service routine. This gets called whenever an I2C interrupt + * Interrupt service routine. This gets called whenever an I2C master interrupt * occurs. */ -static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) +static 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); - if (stat & DW_IC_INTR_TX_ABRT) { dev->cmd_err |= DW_IC_ERR_TX_ABRT; dev->status = STATUS_IDLE; @@ -931,6 +927,22 @@ tx_aborted: 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, "enabled=%#x stat=%#x\n", 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 613dfb8..fd14b41 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -172,6 +172,23 @@ static inline int dw_i2c_acpi_configure(struct platform_device *pdev) } #endif +static void i2c_dw_configure_master(struct dw_i2c_dev *dev) +{ + 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; + } +} + static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare) { if (IS_ERR(i_dev->clk)) @@ -287,19 +304,7 @@ 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(dev); dev->clk = devm_clk_get(&pdev->dev, NULL); if (!i2c_dw_plat_prepare_clk(dev, true)) { -- 2.7.4