| Message ID | 20211018084331.851975-1-luo.penghao@zte.com.cn (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [linux-next] drm/i915/display: Remove unused variable and its assignment. | expand |
On Mon, Oct 18, 2021 at 08:43:31AM +0000, luo penghao wrote: > Variable is not used in functions, and its assignment is redundant too. > So it should be deleted. > > The clang_analyzer complains as follows: > > drivers/gpu/drm/i915/display/intel_dpll.c:1653:2 warning: > Value stored to 'bestm1' is never read. > > drivers/gpu/drm/i915/display/intel_dpll.c:1651:2 warning: > Value stored to 'bestn' is never read. > > Reported-by: Zeal Robot <zealci@zte.com.cn> > Signed-off-by: luo penghao <luo.penghao@zte.com.cn> > --- > drivers/gpu/drm/i915/display/intel_dpll.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c > index b84ed4a..28b1616 100644 > --- a/drivers/gpu/drm/i915/display/intel_dpll.c > +++ b/drivers/gpu/drm/i915/display/intel_dpll.c > @@ -1644,13 +1644,11 @@ static void chv_prepare_pll(const struct intel_crtc_state *crtc_state) > enum pipe pipe = crtc->pipe; > enum dpio_channel port = vlv_pipe_to_channel(pipe); > u32 loopfilter, tribuf_calcntr; > - u32 bestn, bestm1, bestm2, bestp1, bestp2, bestm2_frac; > + u32 bestm2, bestp1, bestp2, bestm2_frac; > u32 dpio_val; > int vco; > > - bestn = crtc_state->dpll.n; This one we could use. For some reason we hardcode it to 1 now, which is correct for our use cases but I don't really see a reason to hardcode it here. We are supposed to calculate it correctly after all, and chv_crtc_clock_get() also just blindly reads it out. > bestm2_frac = crtc_state->dpll.m2 & 0x3fffff; > - bestm1 = crtc_state->dpll.m1; This one is a bit trickier since I don't think the spec even gives us other values. But we could assert that it's correct. Some something along these lines I think would be best: + drm_WARN_ON(&dev_priv->drm, bestm1 != 2); vlv_dpio_write(dev_priv, pipe, CHV_PLL_DW1(port), DPIO_CHV_M1_DIV_BY_2 | - 1 << DPIO_CHV_N_DIV_SHIFT); + bestn << DPIO_CHV_N_DIV_SHIFT);
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diff --git a/drivers/gpu/drm/i915/display/intel_dpll.c b/drivers/gpu/drm/i915/display/intel_dpll.c index b84ed4a..28b1616 100644 --- a/drivers/gpu/drm/i915/display/intel_dpll.c +++ b/drivers/gpu/drm/i915/display/intel_dpll.c @@ -1644,13 +1644,11 @@ static void chv_prepare_pll(const struct intel_crtc_state *crtc_state) enum pipe pipe = crtc->pipe; enum dpio_channel port = vlv_pipe_to_channel(pipe); u32 loopfilter, tribuf_calcntr; - u32 bestn, bestm1, bestm2, bestp1, bestp2, bestm2_frac; + u32 bestm2, bestp1, bestp2, bestm2_frac; u32 dpio_val; int vco; - bestn = crtc_state->dpll.n; bestm2_frac = crtc_state->dpll.m2 & 0x3fffff; - bestm1 = crtc_state->dpll.m1; bestm2 = crtc_state->dpll.m2 >> 22; bestp1 = crtc_state->dpll.p1; bestp2 = crtc_state->dpll.p2;
Variable is not used in functions, and its assignment is redundant too. So it should be deleted. The clang_analyzer complains as follows: drivers/gpu/drm/i915/display/intel_dpll.c:1653:2 warning: Value stored to 'bestm1' is never read. drivers/gpu/drm/i915/display/intel_dpll.c:1651:2 warning: Value stored to 'bestn' is never read. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: luo penghao <luo.penghao@zte.com.cn> --- drivers/gpu/drm/i915/display/intel_dpll.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)