* [PATCH 1/2] i2c: exynos: add support for HSI2C module on Exynos7
2014-09-16 9:33 [PATCH 0/2] i2c: Add i2c support for Exynos7 SoC Naveen Krishna Chatradhi
@ 2014-09-16 9:33 ` Naveen Krishna Chatradhi
2014-10-03 1:34 ` Wolfram Sang
2014-09-16 9:33 ` [PATCH 2/2] i2c: exynos5: Add Kconfig dependencies Naveen Krishna Chatradhi
1 sibling, 1 reply; 5+ messages in thread
From: Naveen Krishna Chatradhi @ 2014-09-16 9:33 UTC (permalink / raw)
To: linux-i2c
Cc: naveenkrishna.ch, linux-arm-kernel, linux-samsung-soc, sjg,
grundler, linux-kernel, wsa, cpgs, devicetree
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 <ch.naveen@samsung.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
---
.../devicetree/bindings/i2c/i2c-exynos5.txt | 2 +
drivers/i2c/busses/i2c-exynos5.c | 71 ++++++++++++++++++--
2 files changed, 67 insertions(+), 6 deletions(-)
diff --git a/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt b/Documentation/devicetree/bindings/i2c/i2c-exynos5.txt
index d4745e3..2dbc0b6 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/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
index 28073f1..81e6263 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);
--
1.7.9.5
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