Re: [PATCH] SPI: Fix distinct pointer types warning for ARCH=MIPS

Hi Nathan,

On Thu, Jan 7, 2021 at 6:31 PM Nathan Chancellor
[off-list ref] wrote:

On Thu, Jan 07, 2021 at 07:57:04PM +0800, Yanteng Si wrote:

quoted

Fix a new warning report by build for make ARCH=MIPS allmodconfig:

drivers/spi/spi-cadence-quadspi.c: In function 'cqspi_direct_read_execute':
 ./include/linux/minmax.h:18:28: warning: comparison of distinct pointer types lacks a cast
    18 |  (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
       |                            ^~
 ./include/linux/minmax.h:32:4: note: in expansion of macro '__typecheck'
    32 |   (__typecheck(x, y) && __no_side_effects(x, y))
       |    ^~~~~~~~~~~
 ./include/linux/minmax.h:42:24: note: in expansion of macro '__safe_cmp'
    42 |  __builtin_choose_expr(__safe_cmp(x, y), \
       |                        ^~~~~~~~~~
 ./include/linux/minmax.h:58:19: note: in expansion of macro '__careful_cmp'
    58 | #define max(x, y) __careful_cmp(x, y, >)
       |                   ^~~~~~~~~~~~~
 drivers/spi/spi-cadence-quadspi.c:1153:24: note: in expansion of macro 'max'
  1153 |       msecs_to_jiffies(max(len, 500UL)))) {
       |                        ^~~

"len" is unsigned,however,"500" is unsigned long.

len is size_t, which us either unsigned int or unsigned long.

quoted

Signed-off-by: Yanteng Si <redacted>
---
 drivers/spi/spi-cadence-quadspi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 06a65e9a8a60..576610ba1118 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c

@@ -1150,7 +1150,7 @@ static int cqspi_direct_read_execute(struct cqspi_flash_pdata *f_pdata,

      dma_async_issue_pending(cqspi->rx_chan);
      if (!wait_for_completion_timeout(&cqspi->rx_dma_complete,
-                                      msecs_to_jiffies(max(len, 500UL)))) {
+                                      msecs_to_jiffies(max(len, 500U)))) {
              dmaengine_terminate_sync(cqspi->rx_chan);
              dev_err(dev, "DMA wait_for_completion_timeout\n");
              ret = -ETIMEDOUT;
--

2.27.0

Isn't this just going to cause warnings on 64-bit platforms now because
size_t is defined as unsigned long and it will now be compared against
unsigned int? This fix should work for everyone, not sure how pretty it

Yes it is!

is though.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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