fifo_depth of the HSI2C is not constant Exynos5420 and Exynos5250 supports fifo_depth of 64bytes Exynos5260 supports fifo_depth of 16bytes.
This patch configures the fifo_depth based on HSI2C modules version. Signed-off-by: Naveen Krishna Chatradhi <ich.nav...@samsung.com> [For finding out the difference and initial contribution] Signed-off-by: Pankaj Dubey <pankaj.du...@samsung.com> --- changes since v3: use variant struct to handle the fifo depths drivers/i2c/busses/i2c-exynos5.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c index 12730d1..5c875c0 100644 --- a/drivers/i2c/busses/i2c-exynos5.c +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -76,12 +76,6 @@ #define HSI2C_RXFIFO_TRIGGER_LEVEL(x) ((x) << 4) #define HSI2C_TXFIFO_TRIGGER_LEVEL(x) ((x) << 16) -/* As per user manual FIFO max depth is 64bytes */ -#define HSI2C_FIFO_MAX 0x40 -/* default trigger levels for Tx and Rx FIFOs */ -#define HSI2C_DEF_TXFIFO_LVL (HSI2C_FIFO_MAX - 0x30) -#define HSI2C_DEF_RXFIFO_LVL (HSI2C_FIFO_MAX - 0x10) - /* I2C_TRAILING_CTL Register bits */ #define HSI2C_TRAILING_COUNT (0xf) @@ -455,7 +449,7 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS); fifo_level = HSI2C_TX_FIFO_LVL(fifo_status); - len = HSI2C_FIFO_MAX - fifo_level; + len = i2c->variant->fifo_depth - fifo_level; if (len > (i2c->msg->len - i2c->msg_ptr)) len = i2c->msg->len - i2c->msg_ptr; @@ -523,6 +517,7 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop) u32 i2c_auto_conf = 0; u32 fifo_ctl; unsigned long flags; + unsigned short trig_lvl; i2c_ctl = readl(i2c->regs + HSI2C_CTL); i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON); @@ -533,13 +528,19 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop) i2c_auto_conf = HSI2C_READ_WRITE; - fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(HSI2C_DEF_TXFIFO_LVL); + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ? + (i2c->variant->fifo_depth * 3/4) : i2c->msg->len; + fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(trig_lvl); + int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN | HSI2C_INT_TRAILING_EN); } else { i2c_ctl |= HSI2C_TXCHON; - fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(HSI2C_DEF_RXFIFO_LVL); + trig_lvl = (i2c->msg->len > i2c->variant->fifo_depth) ? + (i2c->variant->fifo_depth * 1/4) : i2c->msg->len; + fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(trig_lvl); + int_en |= HSI2C_INT_TX_ALMOSTEMPTY_EN; } @@ -731,6 +732,8 @@ static int exynos5_i2c_probe(struct platform_device *pdev) if (ret) goto err_clk; + i2c->variant = exynos5_i2c_get_variant(pdev); + exynos5_i2c_reset(i2c); ret = i2c_add_adapter(&i2c->adap); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/