Minor refactoring

Move loop indexes into loops
Return on errors instead of loop breaks
Some variables cleanup

bridge/it66121.h

@@ -24,7 +24,7 @@
 
 #include "it66121_registers.h"
 
-#define UNUSED(x) (void)(x)
+#define UNUSED(x) ((void)(x))
 
 /* HW defect leading to losing 3 first bytes during EDID read operation */
 #define EDID_LOSS_LEN 3

bridge/it66121_drv.c

@@ -193,7 +193,8 @@ static int it66121_configure_afe(struct it66121_priv *priv, int clock_khz)
 
 static int it66121_wait_ddc_ready(struct it66121_priv *priv)
 {
-	int ret, val;
+	int ret;
+	unsigned int val;
 
 	ret = regmap_field_read_poll_timeout(priv->ddc_done, val, true, EDID_SLEEP, EDID_TIMEOUT);
 	if (ret)
@@ -221,7 +222,7 @@ static int it66121_clear_ddc_fifo(struct it66121_priv *priv)
 
 static int it66121_abort_ddc_ops(struct it66121_priv *priv)
 {
-	int i, ret;
+	int ret;
 
 	/* Prior to DDC abort command there was also a reset of HDCP:
 	 *  1. HDCP_DESIRE clear bit CP DESIRE
@@ -233,7 +234,7 @@ static int it66121_abort_ddc_ops(struct it66121_priv *priv)
 	/* From original driver: According to 2009/01/15 modification by [email protected]
 	 * do abort DDC twice
 	 */
-	for (i = 0; i < 2; i++) {
+	for (int i = 0; i < 2; i++) {
 		ret = regmap_write(priv->regmap, IT66121_DDC_COMMAND, DDC_CMD_ABORT);
 		if (ret)
 			return ret;
@@ -326,9 +327,11 @@ static void it66121_intr_work(struct work_struct *work_item)
 
 static int it66121_get_edid_block(void *context, u8 *buf, unsigned int block, size_t len)
 {
-	int i, ret, offset = block & 1 ? 128 : 0;
+	int ret;
 	size_t remain = len;
-	unsigned int rd_fifo_val, segment = block >> 1;
+	unsigned int val;
+	unsigned int segment = block >> 1;
+	unsigned int offset = block & 1 ? 128 : 0;
 	static const u8 header[EDID_LOSS_LEN] = { 0x00, 0xFF, 0xFF };
 	struct it66121_priv *priv = context;
 
@@ -354,35 +357,36 @@ static int it66121_get_edid_block(void *context, u8 *buf, unsigned int block, si
 		/* Clear DDC FIFO */
 		ret = it66121_clear_ddc_fifo(priv);
 		if (ret)
-			break;
+			return ret;
 
 		ret = regmap_write(priv->regmap, IT66121_DDC_ADDRESS, EDID_DDC_ADDR);
 		if (ret)
-			break;
+			return ret;
 
 		/* Account 3 bytes that will be lost */
 		ret = regmap_write(priv->regmap, IT66121_DDC_OFFSET, offset - EDID_LOSS_LEN);
 		if (ret)
-			break;
+			return ret;
+
 		ret = regmap_write(priv->regmap, IT66121_DDC_SIZE, (unsigned int)size);
 		if (ret)
-			break;
+			return ret;
 		ret = regmap_write(priv->regmap, IT66121_DDC_SEGMENT, segment);
 		if (ret)
-			break;
+			return ret;
 		ret = regmap_write(priv->regmap, IT66121_DDC_COMMAND, DDC_CMD_EDID_READ);
 		if (ret)
-			break;
+			return ret;
 
 		/* Deduct lost bytes when reading from FIFO */
 		size -= EDID_LOSS_LEN;
 
-		for (i = 0; i < size; i++) {
-			ret = regmap_read(priv->regmap, IT66121_DDC_RD_FIFO, &rd_fifo_val);
+		for (int i = 0; i < size; i++) {
+			ret = regmap_read(priv->regmap, IT66121_DDC_RD_FIFO, &val);
 			if (ret)
 				return ret;
 
-			*(buf++) = rd_fifo_val & 0xFF;
+			*(buf++) = val & 0xFF;
 		}
 
 		remain -= size;
@@ -601,7 +605,7 @@ static void it66121_bridge_mode_set(struct drm_bridge *bridge, const struct drm_
 				    const struct drm_display_mode *adjusted_mode)
 
 {
-	int i, ret;
+	int ret;
 	ssize_t frame_size;
 	struct it66121_priv *priv = container_of(bridge, struct it66121_priv, bridge);
 	u8 buf[HDMI_INFOFRAME_SIZE(AVI)];
@@ -658,7 +662,7 @@ static void it66121_bridge_mode_set(struct drm_bridge *bridge, const struct drm_
 	}
 
 	/* Write new AVI infoframe packet */
-	for (i = 0; i < HDMI_AVI_INFOFRAME_SIZE; i++) {
+	for (int i = 0; i < HDMI_AVI_INFOFRAME_SIZE; i++) {
 		ret = regmap_write(priv->regmap, aviinfo_reg[i],
 				   buf[i + HDMI_INFOFRAME_HEADER_SIZE]);
 		if (ret) {
@@ -764,7 +768,7 @@ static int it66121_regs_init(struct it66121_priv *priv, struct i2c_client *clien
 
 static int it66121_i2c_probe(struct i2c_adapter *adapter, unsigned short address)
 {
-	int i, ret;
+	int ret;
 	u8 id_regs[] = { IT66121_VENDOR_ID_1, IT66121_VENDOR_ID_2, IT66121_DEVICE_ID_1,
 			 IT66121_DEVICE_ID_2 };
 	union {
@@ -784,7 +788,7 @@ static int it66121_i2c_probe(struct i2c_adapter *adapter, unsigned short address
 		return -ENODEV;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(id_regs); i++) {
+	for (int i = 0; i < ARRAY_SIZE(id_regs); i++) {
 		struct i2c_msg msgs[] = {
 			{ .addr = address, .flags = 0, .len = 1, .buf = &id_regs[i] },
 			{ .addr = address, .flags = I2C_M_RD, .len = 1, .buf = &id.b[i] }

fl2000.h

@@ -42,7 +42,7 @@
 
 #include "fl2000_registers.h"
 
-#define UNUSED(x) (void)(x)
+#define UNUSED(x) ((void)(x))
 
 /* Known USB interfaces of FL2000 */
 enum fl2000_interface {

fl2000_drm.c

@@ -51,7 +51,8 @@ static const u32 fl2000_pixel_formats[] = {
 
 static unsigned int fl2000_get_bytes_pix(enum usb_device_speed speed, unsigned int pixclock)
 {
-	unsigned int bytes_pix, max_bw;
+	unsigned int bytes_pix;
+	unsigned int max_bw;
 
 	/* Calculate maximum bandwidth, bytes per second */
 	switch (speed) {
@@ -151,12 +152,11 @@ static inline u32 fl2000_pll_get_divisor(u64 clock_mil, u32 vco_clk, u64 *min_pp
 		100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115,
 		116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128
 	};
-	unsigned int divisor_idx;
 	u32 best_divisor = 0;
 
 	/* Iterate over array */
-	for (divisor_idx = 0; divisor_idx < ARRAY_SIZE(divisor_arr); divisor_idx++) {
-		u32 divisor = divisor_arr[divisor_idx];
+	for (int i = 0; i < ARRAY_SIZE(divisor_arr); i++) {
+		u32 divisor = divisor_arr[i];
 		u64 ppm_err = fl2000_pll_ppm_err(clock_mil, vco_clk, divisor);
 
 		if (ppm_err < *min_ppm_err) {
@@ -173,12 +173,10 @@ static u64 fl2000_pll_calc(u64 clock_mil, struct fl2000_pll *pll, u32 *clock_cal
 {
 	static const u32 prescaler_max = 2;
 	static const u32 multiplier_max = 128;
-	u32 prescaler;
-	u32 multiplier;
 	u64 min_ppm_err = (u64)(-1);
 
-	for (prescaler = 1; prescaler <= prescaler_max; prescaler++)
-		for (multiplier = 1; multiplier <= multiplier_max; multiplier++) {
+	for (u32 prescaler = 1; prescaler <= prescaler_max; prescaler++)
+		for (u32 multiplier = 1; multiplier <= multiplier_max; multiplier++) {
 			/* Do not need precision here yet, no 10^6 multiply */
 			u32 vco_clk = FL2000_XTAL / prescaler * multiplier;
 			u32 divisor;
@@ -193,19 +191,17 @@ static u64 fl2000_pll_calc(u64 clock_mil, struct fl2000_pll *pll, u32 *clock_cal
 			pll->prescaler = prescaler;
 			pll->multiplier = multiplier;
 			pll->divisor = divisor;
-			if (vco_clk < 125000000) {
+			if (vco_clk < 125000000)
 				pll->function = 0;
-			} else if (vco_clk < 250000000) {
+			else if (vco_clk < 250000000)
 				pll->function = 1;
-			} else if (vco_clk < 500000000) {
+			else if (vco_clk < 500000000)
 				pll->function = 2;
-			} else {
+			else
 				pll->function = 3;
-			}
 			*clock_calculated = vco_clk / divisor;
 		}
 
-	/* No exact PLL settings found for requested clock */
 	return min_ppm_err;
 }
 
@@ -217,17 +213,15 @@ static int fl2000_mode_calc(const struct drm_display_mode *mode,
 	u64 clock_mil_adjusted;
 	const u64 clock_mil = (u64)mode->clock * 1000 * FL2000_PLL_PRECISION;
 	const int max_h_adjustment = 10;
-	int s, m;
-	int d = 0;
 
 	if (mode->clock * 1000 > FL2000_MAX_PIXCLOCK)
 		return -1;
 
-	/* Try to match pixel clock slightly adjusting htotal value */
-	for (m = 0, s = 0; m <= max_h_adjustment * 2; m++, s = -s) {
-		/* 0, -1, 1, -2, 2, -3, 3, -3, 4, -4, 5, -5, ... */
-		d += m * s;
-
+	/* Try to match pixel clock slightly adjusting htotal value, sequence is:
+	 * 0, -1, 1, -2, 2, -3, 3, -3, 4, -4, 5, -5, ...
+	 * Here, 's' is used for sign, 'm' is used for modulo, and 'd' is the adjustment value
+	 */
+	for (int m = 0, s = 0, d = 0; m <= max_h_adjustment * 2; m++, s = -s, d += m * s) {
 		/* Maximum pixel clock 1GHz, or 10^9Hz. Multiply by 10^6 we get 10^15Hz. Assume
 		 * maximum htotal is 10000 pix (no way) we get 10^19 max value and using u64 which
 		 * is 1.8*10^19 no overflow can occur. Assume all this was checked before
@@ -302,7 +296,8 @@ static void fl2000_display_disable(struct drm_simple_display_pipe *pipe)
 
 static void fb2000_dirty(struct drm_framebuffer *fb, struct drm_rect *rect)
 {
-	int idx, ret;
+	int ret;
+	int idx;
 	struct drm_device *drm = fb->dev;
 	struct fl2000_drm_if *drm_if = drm->dev_private;
 	struct drm_gem_dma_object *dma_obj = drm_fb_dma_get_gem_obj(fb, 0);

fl2000_drv.c

@@ -40,7 +40,6 @@ static struct component_master_ops fl2000_master_ops = {
 
 static int fl2000_compare(struct device *dev, void *data)
 {
-	int i;
 	struct i2c_client *client = i2c_verify_client(dev);
 	static const char *const fl2000_supported_bridges[] = {
 		"it66121", /* IT66121 driver name*/
@@ -52,7 +51,7 @@ static int fl2000_compare(struct device *dev, void *data)
 		return 0;
 
 	/* Check this is a supported DRM bridge */
-	for (i = 0; i < ARRAY_SIZE(fl2000_supported_bridges); i++)
+	for (int i = 0; i < ARRAY_SIZE(fl2000_supported_bridges); i++)
 		if (!strncmp(fl2000_supported_bridges[i], client->name, sizeof(client->name)))
 			return 1; /* Must be not 0 for success */
 

fl2000_i2c.c

@@ -30,7 +30,8 @@ static int fl2000_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, in
 	int ret;
 	bool read;
 	u16 addr;
-	u8 idx, offset;
+	u8 idx;
+	u8 offset;
 	union {
 		u32 w;
 		u8 b[4];