From: Naveen Krishna Ch Date: Tue, 16 Sep 2014 09:33:17 +0000 (+0530) Subject: i2c: exynos: add support for HSI2C module on Exynos7 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=2374a5399b7263eb1afc6b5522a56ebf9f0b8636;p=linux-beck.git i2c: exynos: add support for HSI2C module on Exynos7 The HSI2C module on Exynos7 differs in the transfer status bits. Transfer status bits were moved to INT_ENABLE and INT_STATUS registers This patch adds support for the HSI2C module on Exynos7. 1. Implementes a "hw" field in the variant struct to distinguish the hardware. 2. Updates the dt-new compatible in dt-binding documenation Signed-off-by: Naveen Krishna Chatradhi Signed-off-by: Wolfram Sang --- diff --git a/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt b/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt index d4745e31f5c6..2dbc0b62daa6 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt +++ b/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt @@ -12,6 +12,8 @@ Required properties: on Exynos5250 and Exynos5420 SoCs. -> "samsung,exynos5260-hsi2c", for i2c compatible with HSI2C available on Exynos5260 SoCs. + -> "samsung,exynos7-hsi2c", for i2c compatible with HSI2C available + on Exynos7 SoCs. - reg: physical base address of the controller and length of memory mapped region. diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 2ac87fa3058d..1f3b9cb1faa7 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -465,7 +465,7 @@ config I2C_EG20T config I2C_EXYNOS5 tristate "Exynos5 high-speed I2C driver" - depends on ARCH_EXYNOS5 && OF + depends on ARCH_EXYNOS && OF default y help High-speed I2C controller on Exynos5 based Samsung SoCs. diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c index 28073f1d6d47..81e6263cd7da 100644 --- a/drivers/i2c/busses/i2c-exynos5.c +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -83,7 +83,6 @@ #define HSI2C_INT_TX_ALMOSTEMPTY_EN (1u << 0) #define HSI2C_INT_RX_ALMOSTFULL_EN (1u << 1) #define HSI2C_INT_TRAILING_EN (1u << 6) -#define HSI2C_INT_I2C_EN (1u << 9) /* I2C_INT_STAT Register bits */ #define HSI2C_INT_TX_ALMOSTEMPTY (1u << 0) @@ -95,6 +94,17 @@ #define HSI2C_INT_TRAILING (1u << 6) #define HSI2C_INT_I2C (1u << 9) +#define HSI2C_INT_TRANS_DONE (1u << 7) +#define HSI2C_INT_TRANS_ABORT (1u << 8) +#define HSI2C_INT_NO_DEV_ACK (1u << 9) +#define HSI2C_INT_NO_DEV (1u << 10) +#define HSI2C_INT_TIMEOUT (1u << 11) +#define HSI2C_INT_I2C_TRANS (HSI2C_INT_TRANS_DONE | \ + HSI2C_INT_TRANS_ABORT | \ + HSI2C_INT_NO_DEV_ACK | \ + HSI2C_INT_NO_DEV | \ + HSI2C_INT_TIMEOUT) + /* I2C_FIFO_STAT Register bits */ #define HSI2C_RX_FIFO_EMPTY (1u << 24) #define HSI2C_RX_FIFO_FULL (1u << 23) @@ -143,6 +153,8 @@ #define EXYNOS5_I2C_TIMEOUT (msecs_to_jiffies(1000)) +#define HSI2C_EXYNOS7 BIT(0) + struct exynos5_i2c { struct i2c_adapter adap; unsigned int suspended:1; @@ -192,6 +204,7 @@ struct exynos5_i2c { */ struct exynos_hsi2c_variant { unsigned int fifo_depth; + unsigned int hw; }; static const struct exynos_hsi2c_variant exynos5250_hsi2c_data = { @@ -202,6 +215,11 @@ static const struct exynos_hsi2c_variant exynos5260_hsi2c_data = { .fifo_depth = 16, }; +static const struct exynos_hsi2c_variant exynos7_hsi2c_data = { + .fifo_depth = 16, + .hw = HSI2C_EXYNOS7, +}; + static const struct of_device_id exynos5_i2c_match[] = { { .compatible = "samsung,exynos5-hsi2c", @@ -212,6 +230,9 @@ static const struct of_device_id exynos5_i2c_match[] = { }, { .compatible = "samsung,exynos5260-hsi2c", .data = &exynos5260_hsi2c_data + }, { + .compatible = "samsung,exynos7-hsi2c", + .data = &exynos7_hsi2c_data }, {}, }; MODULE_DEVICE_TABLE(of, exynos5_i2c_match); @@ -256,13 +277,24 @@ static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c, int mode) i2c->hs_clock : i2c->fs_clock; /* + * In case of HSI2C controller in Exynos5 series * FPCLK / FI2C = * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE + * + * In case of HSI2C controllers in Exynos7 series + * FPCLK / FI2C = + * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + FLT_CYCLE + * * utemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) * utemp1 = (TSCLK_L + TSCLK_H + 2) */ t_ftl_cycle = (readl(i2c->regs + HSI2C_CONF) >> 16) & 0x7; - utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle; + utemp0 = (clkin / op_clk) - 8; + + if (i2c->variant->hw == HSI2C_EXYNOS7) + utemp0 -= t_ftl_cycle; + else + utemp0 -= 2 * t_ftl_cycle; /* CLK_DIV max is 256 */ for (div = 0; div < 256; div++) { @@ -407,7 +439,28 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) writel(int_status, i2c->regs + HSI2C_INT_STATUS); /* handle interrupt related to the transfer status */ - if (int_status & HSI2C_INT_I2C) { + if (i2c->variant->hw == HSI2C_EXYNOS7) { + if (int_status & HSI2C_INT_TRANS_DONE) { + i2c->trans_done = 1; + i2c->state = 0; + } else if (int_status & HSI2C_INT_TRANS_ABORT) { + dev_dbg(i2c->dev, "Deal with arbitration lose\n"); + i2c->state = -EAGAIN; + goto stop; + } else if (int_status & HSI2C_INT_NO_DEV_ACK) { + dev_dbg(i2c->dev, "No ACK from device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (int_status & HSI2C_INT_NO_DEV) { + dev_dbg(i2c->dev, "No device\n"); + i2c->state = -ENXIO; + goto stop; + } else if (int_status & HSI2C_INT_TIMEOUT) { + dev_dbg(i2c->dev, "Accessing device timed out\n"); + i2c->state = -EAGAIN; + goto stop; + } + } else if (int_status & HSI2C_INT_I2C) { trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); if (trans_status & HSI2C_NO_DEV_ACK) { dev_dbg(i2c->dev, "No ACK from device\n"); @@ -512,12 +565,17 @@ static int exynos5_i2c_wait_bus_idle(struct exynos5_i2c *i2c) static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop) { u32 i2c_ctl; - u32 int_en = HSI2C_INT_I2C_EN; + u32 int_en = 0; u32 i2c_auto_conf = 0; u32 fifo_ctl; unsigned long flags; unsigned short trig_lvl; + if (i2c->variant->hw == HSI2C_EXYNOS7) + int_en |= HSI2C_INT_I2C_TRANS; + else + int_en |= HSI2C_INT_I2C; + i2c_ctl = readl(i2c->regs + HSI2C_CTL); i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON); fifo_ctl = HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN; @@ -724,12 +782,13 @@ static int exynos5_i2c_probe(struct platform_device *pdev) goto err_clk; } + /* Need to check the variant before setting up. */ + i2c->variant = exynos5_i2c_get_variant(pdev); + ret = exynos5_hsi2c_clock_setup(i2c); if (ret) goto err_clk; - i2c->variant = exynos5_i2c_get_variant(pdev); - exynos5_i2c_reset(i2c); ret = i2c_add_adapter(&i2c->adap);