1 files changed, 72 insertions, 66 deletions

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index 330ffed011e0..bff3479fe122 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -189,8 +189,6 @@ struct stm32f7_i2c_regs {
 /**
  * struct stm32f7_i2c_spec - private i2c specification timing
  * @rate: I2C bus speed (Hz)
- * @rate_min: 80% of I2C bus speed (Hz)
- * @rate_max: 100% of I2C bus speed (Hz)
  * @fall_max: Max fall time of both SDA and SCL signals (ns)
  * @rise_max: Max rise time of both SDA and SCL signals (ns)
  * @hddat_min: Min data hold time (ns)
@@ -201,8 +199,6 @@ struct stm32f7_i2c_regs {
  */
 struct stm32f7_i2c_spec {
 	u32 rate;
-	u32 rate_min;
-	u32 rate_max;
 	u32 fall_max;
 	u32 rise_max;
 	u32 hddat_min;
@@ -214,7 +210,6 @@ struct stm32f7_i2c_spec {
 
 /**
  * struct stm32f7_i2c_setup - private I2C timing setup parameters
- * @speed: I2C speed mode (standard, Fast Plus)
  * @speed_freq: I2C speed frequency  (Hz)
  * @clock_src: I2C clock source frequency (Hz)
  * @rise_time: Rise time (ns)
@@ -224,7 +219,6 @@ struct stm32f7_i2c_spec {
  * @fmp_clr_offset: Fast Mode Plus clear register offset from set register
  */
 struct stm32f7_i2c_setup {
-	enum stm32_i2c_speed speed;
 	u32 speed_freq;
 	u32 clock_src;
 	u32 rise_time;
@@ -287,7 +281,7 @@ struct stm32f7_i2c_msg {
  * @base: virtual memory area
  * @complete: completion of I2C message
  * @clk: hw i2c clock
- * @speed: I2C clock frequency of the controller. Standard, Fast or Fast+
+ * @bus_rate: I2C clock frequency of the controller
  * @msg: Pointer to data to be written
  * @msg_num: number of I2C messages to be executed
  * @msg_id: message identifiant
@@ -314,7 +308,7 @@ struct stm32f7_i2c_dev {
 	void __iomem *base;
 	struct completion complete;
 	struct clk *clk;
-	int speed;
+	unsigned int bus_rate;
 	struct i2c_msg *msg;
 	unsigned int msg_num;
 	unsigned int msg_id;
@@ -342,11 +336,9 @@ struct stm32f7_i2c_dev {
  * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast,
  * and Fast-mode Plus I2C-bus devices
  */
-static struct stm32f7_i2c_spec i2c_specs[] = {
-	[STM32_I2C_SPEED_STANDARD] = {
+static struct stm32f7_i2c_spec stm32f7_i2c_specs[] = {
+	{
 		.rate = I2C_MAX_STANDARD_MODE_FREQ,
-		.rate_min = I2C_MAX_STANDARD_MODE_FREQ * 8 / 10,	/* 80% */
-		.rate_max = I2C_MAX_STANDARD_MODE_FREQ,
 		.fall_max = 300,
 		.rise_max = 1000,
 		.hddat_min = 0,
@@ -355,10 +347,8 @@ static struct stm32f7_i2c_spec i2c_specs[] = {
 		.l_min = 4700,
 		.h_min = 4000,
 	},
-	[STM32_I2C_SPEED_FAST] = {
+	{
 		.rate = I2C_MAX_FAST_MODE_FREQ,
-		.rate_min = I2C_MAX_FAST_MODE_FREQ * 8 / 10,		/* 80% */
-		.rate_max = I2C_MAX_FAST_MODE_FREQ,
 		.fall_max = 300,
 		.rise_max = 300,
 		.hddat_min = 0,
@@ -367,10 +357,8 @@ static struct stm32f7_i2c_spec i2c_specs[] = {
 		.l_min = 1300,
 		.h_min = 600,
 	},
-	[STM32_I2C_SPEED_FAST_PLUS] = {
+	{
 		.rate = I2C_MAX_FAST_MODE_PLUS_FREQ,
-		.rate_min = I2C_MAX_FAST_MODE_PLUS_FREQ * 8 / 10,	/* 80% */
-		.rate_max = I2C_MAX_FAST_MODE_PLUS_FREQ,
 		.fall_max = 100,
 		.rise_max = 120,
 		.hddat_min = 0,
@@ -411,10 +399,23 @@ static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask)
 	stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask);
 }
 
+static struct stm32f7_i2c_spec *stm32f7_get_specs(u32 rate)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(stm32f7_i2c_specs); i++)
+		if (rate <= stm32f7_i2c_specs[i].rate)
+			return &stm32f7_i2c_specs[i];
+
+	return ERR_PTR(-EINVAL);
+}
+
+#define	RATE_MIN(rate)	((rate) * 8 / 10)
 static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 				      struct stm32f7_i2c_setup *setup,
 				      struct stm32f7_i2c_timings *output)
 {
+	struct stm32f7_i2c_spec *specs;
 	u32 p_prev = STM32F7_PRESC_MAX;
 	u32 i2cclk = DIV_ROUND_CLOSEST(NSEC_PER_SEC,
 				       setup->clock_src);
@@ -432,18 +433,19 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 	u16 p, l, a, h;
 	int ret = 0;
 
-	if (setup->speed >= STM32_I2C_SPEED_END) {
-		dev_err(i2c_dev->dev, "speed out of bound {%d/%d}\n",
-			setup->speed, STM32_I2C_SPEED_END - 1);
+	specs = stm32f7_get_specs(setup->speed_freq);
+	if (specs == ERR_PTR(-EINVAL)) {
+		dev_err(i2c_dev->dev, "speed out of bound {%d}\n",
+			setup->speed_freq);
 		return -EINVAL;
 	}
 
-	if ((setup->rise_time > i2c_specs[setup->speed].rise_max) ||
-	    (setup->fall_time > i2c_specs[setup->speed].fall_max)) {
+	if ((setup->rise_time > specs->rise_max) ||
+	    (setup->fall_time > specs->fall_max)) {
 		dev_err(i2c_dev->dev,
 			"timings out of bound Rise{%d>%d}/Fall{%d>%d}\n",
-			setup->rise_time, i2c_specs[setup->speed].rise_max,
-			setup->fall_time, i2c_specs[setup->speed].fall_max);
+			setup->rise_time, specs->rise_max,
+			setup->fall_time, specs->fall_max);
 		return -EINVAL;
 	}
 
@@ -454,12 +456,6 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 		return -EINVAL;
 	}
 
-	if (setup->speed_freq > i2c_specs[setup->speed].rate) {
-		dev_err(i2c_dev->dev, "ERROR: Freq {%d/%d}\n",
-			setup->speed_freq, i2c_specs[setup->speed].rate);
-		return -EINVAL;
-	}
-
 	/*  Analog and Digital Filters */
 	af_delay_min =
 		(setup->analog_filter ?
@@ -469,13 +465,13 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 		 STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0);
 	dnf_delay = setup->dnf * i2cclk;
 
-	sdadel_min = i2c_specs[setup->speed].hddat_min + setup->fall_time -
+	sdadel_min = specs->hddat_min + setup->fall_time -
 		af_delay_min - (setup->dnf + 3) * i2cclk;
 
-	sdadel_max = i2c_specs[setup->speed].vddat_max - setup->rise_time -
+	sdadel_max = specs->vddat_max - setup->rise_time -
 		af_delay_max - (setup->dnf + 4) * i2cclk;
 
-	scldel_min = setup->rise_time + i2c_specs[setup->speed].sudat_min;
+	scldel_min = setup->rise_time + specs->sudat_min;
 
 	if (sdadel_min < 0)
 		sdadel_min = 0;
@@ -530,8 +526,8 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 
 	tsync = af_delay_min + dnf_delay + (2 * i2cclk);
 	s = NULL;
-	clk_max = NSEC_PER_SEC / i2c_specs[setup->speed].rate_min;
-	clk_min = NSEC_PER_SEC / i2c_specs[setup->speed].rate_max;
+	clk_max = NSEC_PER_SEC / RATE_MIN(setup->speed_freq);
+	clk_min = NSEC_PER_SEC / setup->speed_freq;
 
 	/*
 	 * Among Prescaler possibilities discovered above figures out SCL Low
@@ -549,7 +545,7 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 		for (l = 0; l < STM32F7_SCLL_MAX; l++) {
 			u32 tscl_l = (l + 1) * prescaler + tsync;
 
-			if ((tscl_l < i2c_specs[setup->speed].l_min) ||
+			if ((tscl_l < specs->l_min) ||
 			    (i2cclk >=
 			     ((tscl_l - af_delay_min - dnf_delay) / 4))) {
 				continue;
@@ -561,7 +557,7 @@ static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev,
 					setup->rise_time + setup->fall_time;
 
 				if ((tscl >= clk_min) && (tscl <= clk_max) &&
-				    (tscl_h >= i2c_specs[setup->speed].h_min) &&
+				    (tscl_h >= specs->h_min) &&
 				    (i2cclk < tscl_h)) {
 					int clk_error = tscl - i2cbus;
 
@@ -607,6 +603,17 @@ exit:
 	return ret;
 }
 
+static u32 stm32f7_get_lower_rate(u32 rate)
+{
+	int i = ARRAY_SIZE(stm32f7_i2c_specs);
+
+	while (--i)
+		if (stm32f7_i2c_specs[i].rate < rate)
+			break;
+
+	return stm32f7_i2c_specs[i].rate;
+}
+
 static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
 				    struct stm32f7_i2c_setup *setup)
 {
@@ -619,18 +626,15 @@ static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
 
 	i2c_parse_fw_timings(i2c_dev->dev, t, false);
 
-	if (t->bus_freq_hz >= I2C_MAX_FAST_MODE_PLUS_FREQ)
-		i2c_dev->speed = STM32_I2C_SPEED_FAST_PLUS;
-	else if (t->bus_freq_hz >= I2C_MAX_FAST_MODE_FREQ)
-		i2c_dev->speed = STM32_I2C_SPEED_FAST;
-	else
-		i2c_dev->speed = STM32_I2C_SPEED_STANDARD;
+	if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) {
+		dev_err(i2c_dev->dev, "Invalid bus speed (%i>%i)\n",
+			t->bus_freq_hz, I2C_MAX_FAST_MODE_PLUS_FREQ);
+		return -EINVAL;
+	}
 
+	setup->speed_freq = t->bus_freq_hz;
 	i2c_dev->setup.rise_time = t->scl_rise_ns;
 	i2c_dev->setup.fall_time = t->scl_fall_ns;
-
-	setup->speed = i2c_dev->speed;
-	setup->speed_freq = i2c_specs[setup->speed].rate;
 	setup->clock_src = clk_get_rate(i2c_dev->clk);
 
 	if (!setup->clock_src) {
@@ -644,17 +648,13 @@ static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
 		if (ret) {
 			dev_err(i2c_dev->dev,
 				"failed to compute I2C timings.\n");
-			if (i2c_dev->speed > STM32_I2C_SPEED_STANDARD) {
-				i2c_dev->speed--;
-				setup->speed = i2c_dev->speed;
-				setup->speed_freq =
-					i2c_specs[setup->speed].rate;
-				dev_warn(i2c_dev->dev,
-					 "downgrade I2C Speed Freq to (%i)\n",
-					 i2c_specs[setup->speed].rate);
-			} else {
+			if (setup->speed_freq <= I2C_MAX_STANDARD_MODE_FREQ)
 				break;
-			}
+			setup->speed_freq =
+				stm32f7_get_lower_rate(setup->speed_freq);
+			dev_warn(i2c_dev->dev,
+				 "downgrade I2C Speed Freq to (%i)\n",
+				 setup->speed_freq);
 		}
 	} while (ret);
 
@@ -663,13 +663,15 @@ static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev,
 		return ret;
 	}
 
-	dev_dbg(i2c_dev->dev, "I2C Speed(%i), Freq(%i), Clk Source(%i)\n",
-		setup->speed, setup->speed_freq, setup->clock_src);
+	dev_dbg(i2c_dev->dev, "I2C Speed(%i), Clk Source(%i)\n",
+		setup->speed_freq, setup->clock_src);
 	dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n",
 		setup->rise_time, setup->fall_time);
 	dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n",
 		(setup->analog_filter ? "On" : "Off"), setup->dnf);
 
+	i2c_dev->bus_rate = setup->speed_freq;
+
 	return 0;
 }
 
@@ -1462,7 +1464,8 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
 
 	/* NACK received */
 	if (status & STM32F7_I2C_ISR_NACKF) {
-		dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__);
+		dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n",
+			__func__, f7_msg->addr);
 		writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
 		f7_msg->result = -ENXIO;
 	}
@@ -1866,7 +1869,7 @@ static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev,
 {
 	int ret;
 
-	if (i2c_dev->speed != STM32_I2C_SPEED_FAST_PLUS ||
+	if (i2c_dev->bus_rate <= I2C_MAX_FAST_MODE_FREQ ||
 	    IS_ERR_OR_NULL(i2c_dev->regmap))
 		/* Optional */
 		return 0;
@@ -1940,8 +1943,7 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 	if (!i2c_dev)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
+	i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 	if (IS_ERR(i2c_dev->base))
 		return PTR_ERR(i2c_dev->base);
 	phy_addr = (dma_addr_t)res->start;
@@ -1967,7 +1969,8 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 
 	i2c_dev->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(i2c_dev->clk)) {
-		dev_err(&pdev->dev, "Error: Missing controller clock\n");
+		if (PTR_ERR(i2c_dev->clk) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get controller clock\n");
 		return PTR_ERR(i2c_dev->clk);
 	}
 
@@ -1979,8 +1982,10 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 
 	rst = devm_reset_control_get(&pdev->dev, NULL);
 	if (IS_ERR(rst)) {
-		dev_err(&pdev->dev, "Error: Missing controller reset\n");
 		ret = PTR_ERR(rst);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Error: Missing reset ctrl\n");
+
 		goto clk_free;
 	}
 	reset_control_assert(rst);
@@ -2020,7 +2025,8 @@ static int stm32f7_i2c_probe(struct platform_device *pdev)
 	if (ret)
 		goto clk_free;
 
-	if (i2c_dev->speed == STM32_I2C_SPEED_FAST_PLUS) {
+	/* Setup Fast mode plus if necessary */
+	if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) {
 		ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev);
 		if (ret)
 			goto clk_free;