@@ -397,7 +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;
@@ -444,7 +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;
@@ -452,33 +452,22 @@ 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.
*/
- brcr1 = FIELD_PREP(I2C_BRCR_BRCNT1, 0);
- brcr2 = FIELD_PREP(I2C_BRCR_BRCNT2, i2c_clk / (priv->clk_freq * div) + 1);
+ brcr = i2c_clk / (priv->clk_freq * div) + 1;
+
+ 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 */
@@ -1019,11 +1008,14 @@ 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 */
- BRCR value must go into the BRCR1 field when in high-speed mode. It goes into BRCR2 otherwise. - Remove fallback to standard mode if priv->sm > I2C_FREQ_MODE_FAST. - Set SM properly in probe; previously it only checked STANDARD versus FAST. Now we set STANDARD, FAST, FAST_PLUS or HIGH_SPEED. - Remove all comment sections saying we only support low-speeds. Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com> --- drivers/i2c/busses/i2c-nomadik.c | 40 ++++++++++++++++------------------------ 1 file changed, 16 insertions(+), 24 deletions(-)