From 6aa7de059173a986114ac43b8f50b297a86f09a8 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 23 Oct 2017 14:07:29 -0700 Subject: locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland Signed-off-by: Paul E. McKenney Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar --- arch/xtensa/platforms/xtfpga/lcd.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch/xtensa') diff --git a/arch/xtensa/platforms/xtfpga/lcd.c b/arch/xtensa/platforms/xtfpga/lcd.c index 4dc0c1b43f4b..2f7eb66c23ec 100644 --- a/arch/xtensa/platforms/xtfpga/lcd.c +++ b/arch/xtensa/platforms/xtfpga/lcd.c @@ -34,23 +34,23 @@ static void lcd_put_byte(u8 *addr, u8 data) { #ifdef CONFIG_XTFPGA_LCD_8BIT_ACCESS - ACCESS_ONCE(*addr) = data; + WRITE_ONCE(*addr, data); #else - ACCESS_ONCE(*addr) = data & 0xf0; - ACCESS_ONCE(*addr) = (data << 4) & 0xf0; + WRITE_ONCE(*addr, data & 0xf0); + WRITE_ONCE(*addr, (data << 4) & 0xf0); #endif } static int __init lcd_init(void) { - ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; + WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); mdelay(5); - ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; + WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); udelay(200); - ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE8BIT; + WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE8BIT); udelay(50); #ifndef CONFIG_XTFPGA_LCD_8BIT_ACCESS - ACCESS_ONCE(*LCD_INSTR_ADDR) = LCD_DISPLAY_MODE4BIT; + WRITE_ONCE(*LCD_INSTR_ADDR, LCD_DISPLAY_MODE4BIT); udelay(50); lcd_put_byte(LCD_INSTR_ADDR, LCD_DISPLAY_MODE4BIT); udelay(50); -- cgit