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path: root/drivers/i2c/busses/i2c-nomadik.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-nomadik.c')
-rw-r--r--drivers/i2c/busses/i2c-nomadik.c96
1 files changed, 56 insertions, 40 deletions
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 4f41a3c7824d..d2877e4cc28d 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -6,10 +6,10 @@
* I2C master mode controller driver, used in Nomadik 8815
* and Ux500 platforms.
*
- * The Mobileye EyeQ5 platform is also supported; it uses
+ * The Mobileye EyeQ5 and EyeQ6H platforms are also supported; they use
* the same Ux500/DB8500 IP block with two quirks:
* - The memory bus only supports 32-bit accesses.
- * - A register must be configured for the I2C speed mode;
+ * - (only EyeQ5) A register must be configured for the I2C speed mode;
* it is located in a shared register region called OLB.
*
* Author: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
@@ -26,6 +26,7 @@
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
@@ -396,7 +397,7 @@ static u32 load_i2c_mcr_reg(struct nmk_i2c_dev *priv, u16 flags)
*/
static void setup_i2c_controller(struct nmk_i2c_dev *priv)
{
- u32 brcr1, brcr2;
+ u32 brcr;
u32 i2c_clk, div;
u32 ns;
u16 slsu;
@@ -443,7 +444,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *priv)
/*
* The spec says, in case of std. mode the divider is
* 2 whereas it is 3 for fast and fastplus mode of
- * operation. TODO - high speed support.
+ * operation.
*/
div = (priv->clk_freq > I2C_MAX_STANDARD_MODE_FREQ) ? 3 : 2;
@@ -451,30 +452,23 @@ static void setup_i2c_controller(struct nmk_i2c_dev *priv)
* generate the mask for baud rate counters. The controller
* has two baud rate counters. One is used for High speed
* operation, and the other is for std, fast mode, fast mode
- * plus operation. Currently we do not supprt high speed mode
- * so set brcr1 to 0.
+ * plus operation.
+ *
+ * BRCR is a clock divider amount. Pick highest value that
+ * leads to rate strictly below target. Eg when asking for
+ * 400kHz you want a bus rate <=400kHz (and not >=400kHz).
*/
- brcr1 = FIELD_PREP(I2C_BRCR_BRCNT1, 0);
- brcr2 = FIELD_PREP(I2C_BRCR_BRCNT2, i2c_clk / (priv->clk_freq * div));
+ brcr = DIV_ROUND_UP(i2c_clk, priv->clk_freq * div);
+
+ if (priv->sm == I2C_FREQ_MODE_HIGH_SPEED)
+ brcr = FIELD_PREP(I2C_BRCR_BRCNT1, brcr);
+ else
+ brcr = FIELD_PREP(I2C_BRCR_BRCNT2, brcr);
/* set the baud rate counter register */
- writel((brcr1 | brcr2), priv->virtbase + I2C_BRCR);
+ writel(brcr, priv->virtbase + I2C_BRCR);
- /*
- * set the speed mode. Currently we support
- * only standard and fast mode of operation
- * TODO - support for fast mode plus (up to 1Mb/s)
- * and high speed (up to 3.4 Mb/s)
- */
- if (priv->sm > I2C_FREQ_MODE_FAST) {
- dev_err(&priv->adev->dev,
- "do not support this mode defaulting to std. mode\n");
- brcr2 = FIELD_PREP(I2C_BRCR_BRCNT2,
- i2c_clk / (I2C_MAX_STANDARD_MODE_FREQ * 2));
- writel((brcr1 | brcr2), priv->virtbase + I2C_BRCR);
- writel(FIELD_PREP(I2C_CR_SM, I2C_FREQ_MODE_STANDARD),
- priv->virtbase + I2C_CR);
- }
+ /* set the speed mode */
writel(FIELD_PREP(I2C_CR_SM, priv->sm), priv->virtbase + I2C_CR);
/* set the Tx and Rx FIFO threshold */
@@ -542,12 +536,9 @@ static int read_i2c(struct nmk_i2c_dev *priv, u16 flags)
xfer_done = nmk_i2c_wait_xfer_done(priv);
- if (!xfer_done) {
- /* Controller timed out */
- dev_err(&priv->adev->dev, "read from slave 0x%x timed out\n",
- priv->cli.slave_adr);
+ if (!xfer_done)
status = -ETIMEDOUT;
- }
+
return status;
}
@@ -1018,11 +1009,14 @@ static void nmk_i2c_of_probe(struct device_node *np,
if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq))
priv->clk_freq = I2C_MAX_STANDARD_MODE_FREQ;
- /* This driver only supports 'standard' and 'fast' modes of operation. */
if (priv->clk_freq <= I2C_MAX_STANDARD_MODE_FREQ)
priv->sm = I2C_FREQ_MODE_STANDARD;
- else
+ else if (priv->clk_freq <= I2C_MAX_FAST_MODE_FREQ)
priv->sm = I2C_FREQ_MODE_FAST;
+ else if (priv->clk_freq <= I2C_MAX_FAST_MODE_PLUS_FREQ)
+ priv->sm = I2C_FREQ_MODE_FAST_PLUS;
+ else
+ priv->sm = I2C_FREQ_MODE_HIGH_SPEED;
priv->tft = 1; /* Tx FIFO threshold */
priv->rft = 8; /* Rx FIFO threshold */
@@ -1049,8 +1043,6 @@ static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv)
struct regmap *olb;
unsigned int id;
- priv->has_32b_bus = true;
-
olb = syscon_regmap_lookup_by_phandle_args(np, "mobileye,olb", 1, &id);
if (IS_ERR(olb))
return PTR_ERR(olb);
@@ -1071,15 +1063,40 @@ static int nmk_i2c_eyeq5_probe(struct nmk_i2c_dev *priv)
return 0;
}
+#define NMK_I2C_EYEQ_FLAG_32B_BUS BIT(0)
+#define NMK_I2C_EYEQ_FLAG_IS_EYEQ5 BIT(1)
+
+static const struct of_device_id nmk_i2c_eyeq_match_table[] = {
+ {
+ .compatible = "mobileye,eyeq5-i2c",
+ .data = (void *)(NMK_I2C_EYEQ_FLAG_32B_BUS | NMK_I2C_EYEQ_FLAG_IS_EYEQ5),
+ },
+ {
+ .compatible = "mobileye,eyeq6h-i2c",
+ .data = (void *)NMK_I2C_EYEQ_FLAG_32B_BUS,
+ },
+ { /* sentinel */ }
+};
+
static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
{
- int ret = 0;
- struct nmk_i2c_dev *priv;
+ struct i2c_vendor_data *vendor = id->data;
+ u32 max_fifo_threshold = (vendor->fifodepth / 2) - 1;
struct device_node *np = adev->dev.of_node;
+ const struct of_device_id *match;
struct device *dev = &adev->dev;
+ unsigned long match_flags = 0;
+ struct nmk_i2c_dev *priv;
struct i2c_adapter *adap;
- struct i2c_vendor_data *vendor = id->data;
- u32 max_fifo_threshold = (vendor->fifodepth / 2) - 1;
+ int ret = 0;
+
+ /*
+ * We do not want to attach a .of_match_table to our amba driver.
+ * Do not convert to device_get_match_data().
+ */
+ match = of_match_device(nmk_i2c_eyeq_match_table, dev);
+ if (match)
+ match_flags = (unsigned long)match->data;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -1087,10 +1104,10 @@ static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
priv->vendor = vendor;
priv->adev = adev;
- priv->has_32b_bus = false;
+ priv->has_32b_bus = match_flags & NMK_I2C_EYEQ_FLAG_32B_BUS;
nmk_i2c_of_probe(np, priv);
- if (of_device_is_compatible(np, "mobileye,eyeq5-i2c")) {
+ if (match_flags & NMK_I2C_EYEQ_FLAG_IS_EYEQ5) {
ret = nmk_i2c_eyeq5_probe(priv);
if (ret)
return dev_err_probe(dev, ret, "failed OLB lookup\n");
@@ -1194,7 +1211,6 @@ MODULE_DEVICE_TABLE(amba, nmk_i2c_ids);
static struct amba_driver nmk_i2c_driver = {
.drv = {
- .owner = THIS_MODULE,
.name = DRIVER_NAME,
.pm = pm_ptr(&nmk_i2c_pm),
},
generated by cgit (git 2.34.1) at 2025-07-24 07:04:04 +0000