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Replace the loop counter with a jiffies-based timeout (1 second) using time_before(). This ensures consistent delays across architectures. Signed-off-by: Madhumitha Sundar --- Changes in v2: - Switched from loop counter to jiffies + cpu_relax() as requested by Greg KH. --- drivers/staging/sm750fb/sm750_hw.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/drivers/staging/sm750fb/sm750_hw.c b/drivers/staging/sm750fb/sm750_hw.c index ce46f240c..b24d27a77 100644 --- a/drivers/staging/sm750fb/sm750_hw.c +++ b/drivers/staging/sm750fb/sm750_hw.c @@ -523,19 +523,32 @@ int hw_sm750le_de_wait(void) int hw_sm750_de_wait(void) { - int i = 0x10000000; + /* Wait for 1 second (HZ) */ + unsigned long timeout = jiffies + HZ; unsigned int mask = SYSTEM_CTRL_DE_STATUS_BUSY | SYSTEM_CTRL_DE_FIFO_EMPTY | SYSTEM_CTRL_DE_MEM_FIFO_EMPTY; + unsigned int val; - while (i--) { - unsigned int val = peek32(SYSTEM_CTRL); + /* Run while Current Time is BEFORE the Deadline */ + while (time_before(jiffies, timeout)) { + val = peek32(SYSTEM_CTRL); + /* If Not Busy (0) AND Buffers Empty (1), we are good */ if ((val & mask) == (SYSTEM_CTRL_DE_FIFO_EMPTY | SYSTEM_CTRL_DE_MEM_FIFO_EMPTY)) return 0; + + /* Polite pause to save power */ + cpu_relax(); } - /* timeout error */ + + /* Final check in case we succeeded at the last millisecond */ + val = peek32(SYSTEM_CTRL); + if ((val & mask) == + (SYSTEM_CTRL_DE_FIFO_EMPTY | SYSTEM_CTRL_DE_MEM_FIFO_EMPTY)) + return 0; + return -1; } -- 2.43.0