These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / i2c / busses / i2c-sh_mobile.c

diff --git a/kernel/drivers/i2c/busses/i2c-sh_mobile.c b/kernel/drivers/i2c/busses/i2c-sh_mobile.c
index 007818b..7d2bd3e 100644 (file)
--- a/kernel/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/kernel/drivers/i2c/busses/i2c-sh_mobile.c
@@ -150,6 +150,7 @@ struct sh_mobile_i2c_data {
 
 struct sh_mobile_dt_config {
        int clks_per_count;
+       void (*setup)(struct sh_mobile_i2c_data *pd);
 };
 
 #define IIC_FLAG_HAS_ICIC67    (1 << 0)
@@ -164,6 +165,7 @@ struct sh_mobile_dt_config {
 #define ICIC                   0x0c
 #define ICCL                   0x10
 #define ICCH                   0x14
+#define ICSTART                        0x70
 
 /* Register bits */
 #define ICCR_ICE               0x80
@@ -190,6 +192,8 @@ struct sh_mobile_dt_config {
 #define ICIC_WAITE             0x02
 #define ICIC_DTEE              0x01
 
+#define ICSTART_ICSTART                0x10
+
 static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data)
 {
        if (offs == ICIC)
@@ -726,7 +730,8 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
        struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter);
        struct i2c_msg  *msg;
        int err = 0;
-       int i, k;
+       int i;
+       long timeout;
 
        activate_ch(pd);
 
@@ -745,10 +750,10 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
                        i2c_op(pd, OP_START, 0);
 
                /* The interrupt handler takes care of the rest... */
-               k = wait_event_timeout(pd->wait,
+               timeout = wait_event_timeout(pd->wait,
                                       pd->sr & (ICSR_TACK | SW_DONE),
-                                      5 * HZ);
-               if (!k) {
+                                      adapter->timeout);
+               if (!timeout) {
                        dev_err(pd->dev, "Transfer request timed out\n");
                        if (pd->dma_direction != DMA_NONE)
                                sh_mobile_i2c_cleanup_dma(pd);
@@ -782,6 +787,33 @@ static struct i2c_algorithm sh_mobile_i2c_algorithm = {
        .master_xfer    = sh_mobile_i2c_xfer,
 };
 
+/*
+ * r8a7740 chip has lasting errata on I2C I/O pad reset.
+ * this is work-around for it.
+ */
+static void sh_mobile_i2c_r8a7740_workaround(struct sh_mobile_i2c_data *pd)
+{
+       iic_set_clr(pd, ICCR, ICCR_ICE, 0);
+       iic_rd(pd, ICCR); /* dummy read */
+
+       iic_set_clr(pd, ICSTART, ICSTART_ICSTART, 0);
+       iic_rd(pd, ICSTART); /* dummy read */
+
+       udelay(10);
+
+       iic_wr(pd, ICCR, ICCR_SCP);
+       iic_wr(pd, ICSTART, 0);
+
+       udelay(10);
+
+       iic_wr(pd, ICCR, ICCR_TRS);
+       udelay(10);
+       iic_wr(pd, ICCR, 0);
+       udelay(10);
+       iic_wr(pd, ICCR, ICCR_TRS);
+       udelay(10);
+}
+
 static const struct sh_mobile_dt_config default_dt_config = {
        .clks_per_count = 1,
 };
@@ -790,14 +822,21 @@ static const struct sh_mobile_dt_config fast_clock_dt_config = {
        .clks_per_count = 2,
 };
 
+static const struct sh_mobile_dt_config r8a7740_dt_config = {
+       .clks_per_count = 1,
+       .setup = sh_mobile_i2c_r8a7740_workaround,
+};
+
 static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
        { .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
        { .compatible = "renesas,iic-r8a73a4", .data = &fast_clock_dt_config },
+       { .compatible = "renesas,iic-r8a7740", .data = &r8a7740_dt_config },
        { .compatible = "renesas,iic-r8a7790", .data = &fast_clock_dt_config },
        { .compatible = "renesas,iic-r8a7791", .data = &fast_clock_dt_config },
        { .compatible = "renesas,iic-r8a7792", .data = &fast_clock_dt_config },
        { .compatible = "renesas,iic-r8a7793", .data = &fast_clock_dt_config },
        { .compatible = "renesas,iic-r8a7794", .data = &fast_clock_dt_config },
+       { .compatible = "renesas,iic-r8a7795", .data = &fast_clock_dt_config },
        { .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config },
        {},
 };
@@ -885,6 +924,9 @@ static int sh_mobile_i2c_probe(struct platform_device *dev)
 
                        config = match->data;
                        pd->clks_per_count = config->clks_per_count;
+
+                       if (config->setup)
+                               config->setup(pd);
                }
        } else {
                if (pdata && pdata->bus_speed)