[PATCH 0/4] staging: sm750fb: various code cleanups

[PATCH 0/4] staging: sm750fb: various code cleanups

[Ahmet Sezgin Duran]

This series performs several cleanups on the sm750fb staging driver to
improve code readability and remove redundancy.

The changes include:
- Removing unused header includes and blocks.
- Simplifying frequency validation logic using early returns to reduce
  nesting.
- Removing a redundant variable initialization.
- Fixing a minor stylistic issue (double space).

All changes were verified to have no functional impact on the driver.

Ahmet Sezgin Duran (4):
  staging: sm750fb: remove unused includes
  staging: sm750fb: use early returns in frequency checks
  staging: sm750fb: remove unnecessary initialization
  staging: sm750fb: remove double space in assignment

 drivers/staging/sm750fb/ddk750_chip.c  | 153 +++++++++++++------------
 drivers/staging/sm750fb/sm750.c        |  12 --
 drivers/staging/sm750fb/sm750_accel.c  |  16 +--
 drivers/staging/sm750fb/sm750_cursor.c |  15 ---
 drivers/staging/sm750fb/sm750_hw.c     |  17 ---
 5 files changed, 79 insertions(+), 134 deletions(-)

base-commit: 6abf0b2df0b1c2205a4c0591425e6461afa62edb
-- 
2.53.0

[PATCH 1/4] staging: sm750fb: remove unused includes

[Ahmet Sezgin Duran]

Remove unused header file includes from multiple source files to
declutter the include sections.

Also remove the unused CONFIG_MTRR include block after verifying
that no MTRR interfaces are used by the driver.

No functional changes.

Signed-off-by: Ahmet Sezgin Duran <ahmet@sezginduran.net>
---
 drivers/staging/sm750fb/sm750.c        | 12 ------------
 drivers/staging/sm750fb/sm750_accel.c  | 14 --------------
 drivers/staging/sm750fb/sm750_cursor.c | 14 --------------
 drivers/staging/sm750fb/sm750_hw.c     | 17 -----------------
 4 files changed, 57 deletions(-)

diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c
index 996a586a3727..d26e9fab846a 100644
--- a/drivers/staging/sm750fb/sm750.c
+++ b/drivers/staging/sm750fb/sm750.c
@@ -1,19 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/aperture.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
 #include <linux/fb.h>
-#include <linux/ioport.h>
-#include <linux/init.h>
 #include <linux/pci.h>
-#include <linux/mm_types.h>
-#include <linux/vmalloc.h>
-#include <linux/pagemap.h>
 #include <linux/console.h>
 
 #include "sm750.h"
diff --git a/drivers/staging/sm750fb/sm750_accel.c b/drivers/staging/sm750fb/sm750_accel.c
index ec2f0a6aa57d..f695a2a61c28 100644
--- a/drivers/staging/sm750fb/sm750_accel.c
+++ b/drivers/staging/sm750fb/sm750_accel.c
@@ -1,19 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
 #include <linux/fb.h>
-#include <linux/ioport.h>
-#include <linux/init.h>
-#include <linux/pci.h>
-#include <linux/vmalloc.h>
-#include <linux/pagemap.h>
-#include <linux/console.h>
-#include <linux/platform_device.h>
 
 #include "sm750.h"
 #include "sm750_accel.h"
diff --git a/drivers/staging/sm750fb/sm750_cursor.c b/drivers/staging/sm750fb/sm750_cursor.c
index f0338e6e76b1..9d6bca3106f4 100644
--- a/drivers/staging/sm750fb/sm750_cursor.c
+++ b/drivers/staging/sm750fb/sm750_cursor.c
@@ -1,19 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
 #include <linux/fb.h>
-#include <linux/ioport.h>
-#include <linux/init.h>
-#include <linux/pci.h>
-#include <linux/vmalloc.h>
-#include <linux/pagemap.h>
-#include <linux/console.h>
-#include <linux/platform_device.h>
 
 #include "sm750.h"
 #include "sm750_cursor.h"
diff --git a/drivers/staging/sm750fb/sm750_hw.c b/drivers/staging/sm750fb/sm750_hw.c
index 6f7c354a34a1..34a837fb4b64 100644
--- a/drivers/staging/sm750fb/sm750_hw.c
+++ b/drivers/staging/sm750fb/sm750_hw.c
@@ -1,23 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/delay.h>
 #include <linux/fb.h>
-#include <linux/ioport.h>
-#include <linux/init.h>
 #include <linux/pci.h>
-#include <linux/vmalloc.h>
-#include <linux/pagemap.h>
-#include <linux/console.h>
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
-#endif
-#include <linux/platform_device.h>
-#include <linux/sizes.h>
 
 #include "sm750.h"
 #include "ddk750.h"
-- 
2.53.0

[PATCH 2/4] staging: sm750fb: use early returns in frequency checks

[Ahmet Sezgin Duran]

Invert the frequency validation conditions and use early returns
to reduce nesting and improve readability.

No functional changes.

Signed-off-by: Ahmet Sezgin Duran <ahmet@sezginduran.net>
---
 drivers/staging/sm750fb/ddk750_chip.c | 153 +++++++++++++-------------
 1 file changed, 78 insertions(+), 75 deletions(-)

diff --git a/drivers/staging/sm750fb/ddk750_chip.c b/drivers/staging/sm750fb/ddk750_chip.c
index 136692b00804..0bb56bbec43f 100644
--- a/drivers/staging/sm750fb/ddk750_chip.c
+++ b/drivers/staging/sm750fb/ddk750_chip.c
@@ -61,25 +61,26 @@ static void set_chip_clock(unsigned int frequency)
 	if (sm750_get_chip_type() == SM750LE)
 		return;
 
-	if (frequency) {
-		/*
-		 * Set up PLL structure to hold the value to be set in clocks.
-		 */
-		pll.input_freq = DEFAULT_INPUT_CLOCK; /* Defined in CLOCK.H */
-		pll.clock_type = MXCLK_PLL;
+	if (!frequency)
+		return;
 
-		/*
-		 * Call sm750_calc_pll_value() to fill the other fields
-		 * of the PLL structure. Sometimes, the chip cannot set
-		 * up the exact clock required by the User.
-		 * Return value of sm750_calc_pll_value gives the actual
-		 * possible clock.
-		 */
-		sm750_calc_pll_value(frequency, &pll);
+	/*
+	 * Set up PLL structure to hold the value to be set in clocks.
+	 */
+	pll.input_freq = DEFAULT_INPUT_CLOCK; /* Defined in CLOCK.H */
+	pll.clock_type = MXCLK_PLL;
 
-		/* Master Clock Control: MXCLK_PLL */
-		poke32(MXCLK_PLL_CTRL, sm750_format_pll_reg(&pll));
-	}
+	/*
+	 * Call sm750_calc_pll_value() to fill the other fields
+	 * of the PLL structure. Sometimes, the chip cannot set
+	 * up the exact clock required by the User.
+	 * Return value of sm750_calc_pll_value gives the actual
+	 * possible clock.
+	 */
+	sm750_calc_pll_value(frequency, &pll);
+
+	/* Master Clock Control: MXCLK_PLL */
+	poke32(MXCLK_PLL_CTRL, sm750_format_pll_reg(&pll));
 }
 
 static void set_memory_clock(unsigned int frequency)
@@ -93,37 +94,38 @@ static void set_memory_clock(unsigned int frequency)
 	if (sm750_get_chip_type() == SM750LE)
 		return;
 
-	if (frequency) {
-		/*
-		 * Set the frequency to the maximum frequency
-		 * that the DDR Memory can take which is 336MHz.
-		 */
-		if (frequency > MHz(336))
-			frequency = MHz(336);
-
-		/* Calculate the divisor */
-		divisor = DIV_ROUND_CLOSEST(get_mxclk_freq(), frequency);
-
-		/* Set the corresponding divisor in the register. */
-		reg = peek32(CURRENT_GATE) & ~CURRENT_GATE_M2XCLK_MASK;
-		switch (divisor) {
-		default:
-		case 1:
-			reg |= CURRENT_GATE_M2XCLK_DIV_1;
-			break;
-		case 2:
-			reg |= CURRENT_GATE_M2XCLK_DIV_2;
-			break;
-		case 3:
-			reg |= CURRENT_GATE_M2XCLK_DIV_3;
-			break;
-		case 4:
-			reg |= CURRENT_GATE_M2XCLK_DIV_4;
-			break;
-		}
+	if (!frequency)
+		return;
+
+	/*
+	 * Set the frequency to the maximum frequency
+	 * that the DDR Memory can take which is 336MHz.
+	 */
+	if (frequency > MHz(336))
+		frequency = MHz(336);
+
+	/* Calculate the divisor */
+	divisor = DIV_ROUND_CLOSEST(get_mxclk_freq(), frequency);
 
-		sm750_set_current_gate(reg);
+	/* Set the corresponding divisor in the register. */
+	reg = peek32(CURRENT_GATE) & ~CURRENT_GATE_M2XCLK_MASK;
+	switch (divisor) {
+	default:
+	case 1:
+		reg |= CURRENT_GATE_M2XCLK_DIV_1;
+		break;
+	case 2:
+		reg |= CURRENT_GATE_M2XCLK_DIV_2;
+		break;
+	case 3:
+		reg |= CURRENT_GATE_M2XCLK_DIV_3;
+		break;
+	case 4:
+		reg |= CURRENT_GATE_M2XCLK_DIV_4;
+		break;
 	}
+
+	sm750_set_current_gate(reg);
 }
 
 /*
@@ -145,37 +147,38 @@ static void set_master_clock(unsigned int frequency)
 	if (sm750_get_chip_type() == SM750LE)
 		return;
 
-	if (frequency) {
-		/*
-		 * Set the frequency to the maximum frequency
-		 * that the SM750 engine can run, which is about 190 MHz.
-		 */
-		if (frequency > MHz(190))
-			frequency = MHz(190);
-
-		/* Calculate the divisor */
-		divisor = DIV_ROUND_CLOSEST(get_mxclk_freq(), frequency);
-
-		/* Set the corresponding divisor in the register. */
-		reg = peek32(CURRENT_GATE) & ~CURRENT_GATE_MCLK_MASK;
-		switch (divisor) {
-		default:
-		case 3:
-			reg |= CURRENT_GATE_MCLK_DIV_3;
-			break;
-		case 4:
-			reg |= CURRENT_GATE_MCLK_DIV_4;
-			break;
-		case 6:
-			reg |= CURRENT_GATE_MCLK_DIV_6;
-			break;
-		case 8:
-			reg |= CURRENT_GATE_MCLK_DIV_8;
-			break;
-		}
+	if (!frequency)
+		return;
+
+	/*
+	 * Set the frequency to the maximum frequency
+	 * that the SM750 engine can run, which is about 190 MHz.
+	 */
+	if (frequency > MHz(190))
+		frequency = MHz(190);
+
+	/* Calculate the divisor */
+	divisor = DIV_ROUND_CLOSEST(get_mxclk_freq(), frequency);
 
-		sm750_set_current_gate(reg);
+	/* Set the corresponding divisor in the register. */
+	reg = peek32(CURRENT_GATE) & ~CURRENT_GATE_MCLK_MASK;
+	switch (divisor) {
+	default:
+	case 3:
+		reg |= CURRENT_GATE_MCLK_DIV_3;
+		break;
+	case 4:
+		reg |= CURRENT_GATE_MCLK_DIV_4;
+		break;
+	case 6:
+		reg |= CURRENT_GATE_MCLK_DIV_6;
+		break;
+	case 8:
+		reg |= CURRENT_GATE_MCLK_DIV_8;
+		break;
 	}
+
+	sm750_set_current_gate(reg);
 }
 
 unsigned int ddk750_get_vm_size(void)
-- 
2.53.0

[PATCH 3/4] staging: sm750fb: remove unnecessary initialization

[Ahmet Sezgin Duran]

Remove `data = 0` initialization since the variable is reset each
time in the for loop.

Signed-off-by: Ahmet Sezgin Duran <ahmet@sezginduran.net>
---
 drivers/staging/sm750fb/sm750_cursor.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/staging/sm750fb/sm750_cursor.c b/drivers/staging/sm750fb/sm750_cursor.c
index 9d6bca3106f4..f822d147ede9 100644
--- a/drivers/staging/sm750fb/sm750_cursor.c
+++ b/drivers/staging/sm750fb/sm750_cursor.c
@@ -84,7 +84,6 @@ void sm750_hw_cursor_set_data(struct lynx_cursor *cursor, u16 rop,
 	/* in byte */
 	offset = cursor->max_w * 2 / 8;
 
-	data = 0;
 	pstart = cursor->vstart;
 	pbuffer = pstart;
 
-- 
2.53.0

[PATCH 4/4] staging: sm750fb: remove double space in assignment

[Ahmet Sezgin Duran]

Remove extra space after `=` in assignment of `reg` variable.

Signed-off-by: Ahmet Sezgin Duran <ahmet@sezginduran.net>
---
 drivers/staging/sm750fb/sm750_accel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/sm750fb/sm750_accel.c b/drivers/staging/sm750fb/sm750_accel.c
index f695a2a61c28..e3225c0c320b 100644
--- a/drivers/staging/sm750fb/sm750_accel.c
+++ b/drivers/staging/sm750fb/sm750_accel.c
@@ -26,7 +26,7 @@ void sm750_hw_de_init(struct lynx_accel *accel)
 	write_dpr(accel, DE_MASKS, 0xFFFFFFFF);
 
 	/* dpr1c */
-	reg =  0x3;
+	reg = 0x3;
 
 	clr = DE_STRETCH_FORMAT_PATTERN_XY |
 	      DE_STRETCH_FORMAT_PATTERN_Y_MASK |
-- 
2.53.0