Re: [PATCH v2] staging: rts5208: Clean up coding style in rtsx_chip.c to get rid of checkpatch.pl warnings and combine two ifs into one

[Joe Perches <joe@perches.com>]

On Thu, 2014-10-02 at 14:13 +0300, Giedrius Statkevicius wrote:
> Fix 10 occurences of coding style errors where the line exceeds 80 characters by breaking them into more lines.
> Checkpatch.pl reports these errors as: 'WARNING: line over 80 characters'
> Also, removes unnecessary returns in two void functions by removing the return statements.
> Checkpatch.pl reports these errors as: 'WARNING: void function return statements are not generally useful'
> Lastly it combines two if statements into one in rtsx_reset_chip()

Another way to reduce indentation is to write another
utility function like the suggested patch at the end
of this email.

Also, changing:

	if (foo) {
		[short code block...]
	} else
		[long code block...]
	}

	return bar;
to:
	if (foo) {
		[short code block...]
		return bar;
	}

	[long code block...]
	return bar;

reduces indentation.

Al Viro once gave good advice about indentation here:
https://lkml.org/lkml/2013/3/20/345

Using ternaries can also reduce line count and
indentation:
	if (something)
		foo(bar, 1, ...);
	else
		foo(bar, 2, ...);
can be written
	foo(bar, something ? 1 : 2, ...)

Here's a suggestion:
---
 drivers/staging/rts5208/rtsx_chip.c | 71 ++++++++++++++++++++-----------------
 1 file changed, 38 insertions(+), 33 deletions(-)

diff --git a/drivers/staging/rts5208/rtsx_chip.c b/drivers/staging/rts5208/rtsx_chip.c
index 1411471..85d670d 100644
--- a/drivers/staging/rts5208/rtsx_chip.c
+++ b/drivers/staging/rts5208/rtsx_chip.c
@@ -226,6 +226,43 @@ static int rtsx_pre_handle_sdio_new(struct rtsx_chip *chip)
 }
 #endif
 
+static int rtsx_reset_aspm(struct rtsx_chip *chip)
+{
+	int rtn = STATUS_SUCCESS;
+
+	if (chip->dynamic_aspm) {
+		if (CHK_SDIO_EXIST(chip) && CHECK_PID(chip, 0x5288)) {
+			rtn = rtsx_write_cfg_dw(chip, 2, 0xC0, 0xFF,
+						chip->aspm_l0s_l1_en);
+			if (rtn != STATUS_SUCCESS)
+				TRACE_RET(chip, STATUS_FAIL);
+		}
+		return rtn;
+	}
+
+	if (CHECK_PID(chip, 0x5208))
+		RTSX_WRITE_REG(chip, ASPM_FORCE_CTL, 0xFF, 0x3F);
+
+	rtn = rtsx_write_config_byte(chip, LCTLR, chip->aspm_l0s_l1_en);
+	if (rtn != STATUS_SUCCESS)
+		TRACE_RET(chip, STATUS_FAIL);
+
+	chip->aspm_level[0] = chip->aspm_l0s_l1_en;
+
+	if (CHK_SDIO_EXIST(chip)) {
+		chip->aspm_level[1] = chip->aspm_l0s_l1_en;
+		rtn = rtsx_write_cfg_dw(chip,
+					CHECK_PID(chip, 0x5288) ? 2 : 1,
+					0xC0, 0xFF, chip->aspm_l0s_l1_en);
+		if (rtn != STATUS_SUCCESS)
+			TRACE_RET(chip, STATUS_FAIL);
+	}
+
+	chip->aspm_enabled = 1;
+
+	return rtn;
+}
+
 int rtsx_reset_chip(struct rtsx_chip *chip)
 {
 	int retval;
@@ -288,39 +325,7 @@ int rtsx_reset_chip(struct rtsx_chip *chip)
 
 	/* Enable ASPM */
 	if (chip->aspm_l0s_l1_en) {
-		if (chip->dynamic_aspm) {
-			if (CHK_SDIO_EXIST(chip)) {
-				if (CHECK_PID(chip, 0x5288)) {
-					retval = rtsx_write_cfg_dw(chip, 2, 0xC0, 0xFF, chip->aspm_l0s_l1_en);
-					if (retval != STATUS_SUCCESS)
-						TRACE_RET(chip, STATUS_FAIL);
-				}
-			}
-		} else {
-			if (CHECK_PID(chip, 0x5208))
-				RTSX_WRITE_REG(chip, ASPM_FORCE_CTL,
-					0xFF, 0x3F);
-
-			retval = rtsx_write_config_byte(chip, LCTLR,
-							chip->aspm_l0s_l1_en);
-			if (retval != STATUS_SUCCESS)
-				TRACE_RET(chip, STATUS_FAIL);
-
-			chip->aspm_level[0] = chip->aspm_l0s_l1_en;
-			if (CHK_SDIO_EXIST(chip)) {
-				chip->aspm_level[1] = chip->aspm_l0s_l1_en;
-				if (CHECK_PID(chip, 0x5288))
-					retval = rtsx_write_cfg_dw(chip, 2, 0xC0, 0xFF, chip->aspm_l0s_l1_en);
-				else
-					retval = rtsx_write_cfg_dw(chip, 1, 0xC0, 0xFF, chip->aspm_l0s_l1_en);
-
-				if (retval != STATUS_SUCCESS)
-					TRACE_RET(chip, STATUS_FAIL);
-
-			}
-
-			chip->aspm_enabled = 1;
-		}
+		retval = rtsx_reset_aspm(chip);
 	} else {
 		if (chip->asic_code && CHECK_PID(chip, 0x5208)) {
 			retval = rtsx_write_phy_register(chip, 0x07, 0x0129);