Hi Dmitry, Thanks for the report. On 10/22/19 02:29, Dmitry Vyukov wrote: > Hi Kieran, > > Building kernel with clang gives me: > > drivers/media/i2c/adv748x/adv748x-afe.c:452:12: warning: operator '?:' > has lower precedence than '|'; '|' will be evaluated first > [-Wbitwise-conditional-parentheses] > > ret = sdp_clrset(state, ADV748X_SDP_FRP, ADV748X_SDP_FRP_MASK, enable > ? ctrl->val - 1 : 0); > #define sdp_clrset(s, r, m, v) sdp_write(s, r, (sdp_read(s, r) & ~m) | v) > > This is on linux-next commit a722f75b2923b4fd44c17e7255e822ac48fe85f0 > Date: Tue Oct 22 16:17:17 2019 +1100 > Add linux-next specific files for 20191022 > > It seems sdp_clrset needs some more parens. > Yep. It seems this is enough to fix the issue: diff --git a/drivers/media/i2c/adv748x/adv748x.h b/drivers/media/i2c/adv748x/adv748x.h index 5042f9e94aee..fccb388ce179 100644 --- a/drivers/media/i2c/adv748x/adv748x.h +++ b/drivers/media/i2c/adv748x/adv748x.h @@ -394,10 +394,10 @@ int adv748x_write_block(struct adv748x_state *state, int client_page, #define io_read(s, r) adv748x_read(s, ADV748X_PAGE_IO, r) #define io_write(s, r, v) adv748x_write(s, ADV748X_PAGE_IO, r, v) -#define io_clrset(s, r, m, v) io_write(s, r, (io_read(s, r) & ~m) | v) +#define io_clrset(s, r, m, v) io_write(s, r, (io_read(s, r) & ~(m)) | (v)) #define hdmi_read(s, r) adv748x_read(s, ADV748X_PAGE_HDMI, r) -#define hdmi_read16(s, r, m) (((hdmi_read(s, r) << 8) | hdmi_read(s, r+1)) & m) +#define hdmi_read16(s, r, m) (((hdmi_read(s, r) << 8) | hdmi_read(s, (r)+1)) & (m)) #define hdmi_write(s, r, v) adv748x_write(s, ADV748X_PAGE_HDMI, r, v) #define repeater_read(s, r) adv748x_read(s, ADV748X_PAGE_REPEATER, r) @@ -405,11 +405,11 @@ int adv748x_write_block(struct adv748x_state *state, int client_page, #define sdp_read(s, r) adv748x_read(s, ADV748X_PAGE_SDP, r) #define sdp_write(s, r, v) adv748x_write(s, ADV748X_PAGE_SDP, r, v) -#define sdp_clrset(s, r, m, v) sdp_write(s, r, (sdp_read(s, r) & ~m) | v) +#define sdp_clrset(s, r, m, v) sdp_write(s, r, (sdp_read(s, r) & ~(m)) | (v)) #define cp_read(s, r) adv748x_read(s, ADV748X_PAGE_CP, r) #define cp_write(s, r, v) adv748x_write(s, ADV748X_PAGE_CP, r, v) -#define cp_clrset(s, r, m, v) cp_write(s, r, (cp_read(s, r) & ~m) | v) +#define cp_clrset(s, r, m, v) cp_write(s, r, (cp_read(s, r) & ~(m)) | (v)) #define tx_read(t, r) adv748x_read(t->state, t->page, r) #define tx_write(t, r, v) adv748x_write(t->state, t->page, r, v) More on writing safe macros in C: https://wiki.sei.cmu.edu/confluence/display/c/PRE31-C.+Avoid+side+effects+in+arguments+to+unsafe+macros -- Gustavo
