BCC: l...@intel.com CC: kbuild-...@lists.01.org In-Reply-To: <20220819085703.4161266-4-conor.doo...@microchip.com> References: <20220819085703.4161266-4-conor.doo...@microchip.com> TO: Conor Dooley <conor.doo...@microchip.com> TO: Thierry Reding <thierry.red...@gmail.com> TO: "Uwe Kleine-König" <u.kleine-koe...@pengutronix.de> TO: Rob Herring <robh...@kernel.org> TO: Krzysztof Kozlowski <k...@kernel.org> CC: Daire McNamara <daire.mcnam...@microchip.com> CC: devicet...@vger.kernel.org CC: linux-ker...@vger.kernel.org CC: linux-...@vger.kernel.org CC: linux-ri...@lists.infradead.org CC: Conor Dooley <conor.doo...@microchip.com>
Hi Conor, I love your patch! Perhaps something to improve: [auto build test WARNING on 568035b01cfb107af8d2e4bd2fb9aea22cf5b868] url: https://github.com/intel-lab-lkp/linux/commits/Conor-Dooley/Microchip-soft-ip-corePWM-driver/20220819-170106 base: 568035b01cfb107af8d2e4bd2fb9aea22cf5b868 :::::: branch date: 2 days ago :::::: commit date: 2 days ago config: arm64-randconfig-m031-20220821 (https://download.01.org/0day-ci/archive/20220821/202208212329.xetz1mt0-...@intel.com/config) compiler: aarch64-linux-gcc (GCC) 12.1.0 If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <l...@intel.com> Reported-by: Dan Carpenter <dan.carpen...@oracle.com> smatch warnings: drivers/pwm/pwm-microchip-core.c:295 mchp_core_pwm_apply() warn: inconsistent returns '&mchp_core_pwm->lock'. vim +295 drivers/pwm/pwm-microchip-core.c ae39414af22131 Conor Dooley 2022-08-19 199 ae39414af22131 Conor Dooley 2022-08-19 200 static int mchp_core_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, ae39414af22131 Conor Dooley 2022-08-19 201 const struct pwm_state *state) ae39414af22131 Conor Dooley 2022-08-19 202 { ae39414af22131 Conor Dooley 2022-08-19 203 struct mchp_core_pwm_chip *mchp_core_pwm = to_mchp_core_pwm(chip); ae39414af22131 Conor Dooley 2022-08-19 204 struct pwm_state current_state = pwm->state; ae39414af22131 Conor Dooley 2022-08-19 205 bool period_locked; ae39414af22131 Conor Dooley 2022-08-19 206 u64 duty_steps; ae39414af22131 Conor Dooley 2022-08-19 207 u16 prescale; ae39414af22131 Conor Dooley 2022-08-19 208 u8 period_steps; ae39414af22131 Conor Dooley 2022-08-19 209 int ret; ae39414af22131 Conor Dooley 2022-08-19 210 ae39414af22131 Conor Dooley 2022-08-19 211 mutex_lock(&mchp_core_pwm->lock); ae39414af22131 Conor Dooley 2022-08-19 212 ae39414af22131 Conor Dooley 2022-08-19 213 if (!state->enabled) { ae39414af22131 Conor Dooley 2022-08-19 214 mchp_core_pwm_enable(chip, pwm, false, current_state.period); ae39414af22131 Conor Dooley 2022-08-19 215 mutex_unlock(&mchp_core_pwm->lock); ae39414af22131 Conor Dooley 2022-08-19 216 return 0; ae39414af22131 Conor Dooley 2022-08-19 217 } ae39414af22131 Conor Dooley 2022-08-19 218 ae39414af22131 Conor Dooley 2022-08-19 219 /* ae39414af22131 Conor Dooley 2022-08-19 220 * If the only thing that has changed is the duty cycle or the polarity, ae39414af22131 Conor Dooley 2022-08-19 221 * we can shortcut the calculations and just compute/apply the new duty ae39414af22131 Conor Dooley 2022-08-19 222 * cycle pos & neg edges ae39414af22131 Conor Dooley 2022-08-19 223 * As all the channels share the same period, do not allow it to be ae39414af22131 Conor Dooley 2022-08-19 224 * changed if any other channels are enabled. ae39414af22131 Conor Dooley 2022-08-19 225 * If the period is locked, it may not be possible to use a period ae39414af22131 Conor Dooley 2022-08-19 226 * less than that requested. In that case, we just abort. ae39414af22131 Conor Dooley 2022-08-19 227 */ ae39414af22131 Conor Dooley 2022-08-19 228 period_locked = mchp_core_pwm->channel_enabled & ~(1 << pwm->hwpwm); ae39414af22131 Conor Dooley 2022-08-19 229 ae39414af22131 Conor Dooley 2022-08-19 230 if (period_locked) { ae39414af22131 Conor Dooley 2022-08-19 231 u16 hw_prescale; ae39414af22131 Conor Dooley 2022-08-19 232 u8 hw_period_steps; ae39414af22131 Conor Dooley 2022-08-19 233 ae39414af22131 Conor Dooley 2022-08-19 234 mchp_core_pwm_calc_period(chip, state, (u8 *)&prescale, &period_steps); ae39414af22131 Conor Dooley 2022-08-19 235 hw_prescale = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PRESCALE); ae39414af22131 Conor Dooley 2022-08-19 236 hw_period_steps = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PERIOD); ae39414af22131 Conor Dooley 2022-08-19 237 ae39414af22131 Conor Dooley 2022-08-19 238 if ((period_steps + 1) * (prescale + 1) < ae39414af22131 Conor Dooley 2022-08-19 239 (hw_period_steps + 1) * (hw_prescale + 1)) { ae39414af22131 Conor Dooley 2022-08-19 240 mutex_unlock(&mchp_core_pwm->lock); ae39414af22131 Conor Dooley 2022-08-19 241 return -EINVAL; ae39414af22131 Conor Dooley 2022-08-19 242 } ae39414af22131 Conor Dooley 2022-08-19 243 ae39414af22131 Conor Dooley 2022-08-19 244 /* ae39414af22131 Conor Dooley 2022-08-19 245 * It is possible that something could have set the period_steps ae39414af22131 Conor Dooley 2022-08-19 246 * register to 0xff, which would prevent us from setting a 100% ae39414af22131 Conor Dooley 2022-08-19 247 * duty cycle, as explained in the mchp_core_pwm_calc_period() ae39414af22131 Conor Dooley 2022-08-19 248 * above. ae39414af22131 Conor Dooley 2022-08-19 249 * The period is locked and we cannot change this, so we abort. ae39414af22131 Conor Dooley 2022-08-19 250 */ ae39414af22131 Conor Dooley 2022-08-19 251 if (period_steps == MCHPCOREPWM_PERIOD_STEPS_MAX) ae39414af22131 Conor Dooley 2022-08-19 252 return -EINVAL; ae39414af22131 Conor Dooley 2022-08-19 253 ae39414af22131 Conor Dooley 2022-08-19 254 prescale = hw_prescale; ae39414af22131 Conor Dooley 2022-08-19 255 period_steps = hw_period_steps; ae39414af22131 Conor Dooley 2022-08-19 256 } else if (!current_state.enabled || current_state.period != state->period) { ae39414af22131 Conor Dooley 2022-08-19 257 ret = mchp_core_pwm_calc_period(chip, state, (u8 *)&prescale, &period_steps); ae39414af22131 Conor Dooley 2022-08-19 258 if (ret) { ae39414af22131 Conor Dooley 2022-08-19 259 mutex_unlock(&mchp_core_pwm->lock); ae39414af22131 Conor Dooley 2022-08-19 260 return ret; ae39414af22131 Conor Dooley 2022-08-19 261 } ae39414af22131 Conor Dooley 2022-08-19 262 mchp_core_pwm_apply_period(mchp_core_pwm, prescale, period_steps); ae39414af22131 Conor Dooley 2022-08-19 263 } else { ae39414af22131 Conor Dooley 2022-08-19 264 prescale = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PRESCALE); ae39414af22131 Conor Dooley 2022-08-19 265 period_steps = readb_relaxed(mchp_core_pwm->base + MCHPCOREPWM_PERIOD); ae39414af22131 Conor Dooley 2022-08-19 266 ae39414af22131 Conor Dooley 2022-08-19 267 /* ae39414af22131 Conor Dooley 2022-08-19 268 * As above, it is possible that something could have set the ae39414af22131 Conor Dooley 2022-08-19 269 * period_steps register to 0xff, which would prevent us from ae39414af22131 Conor Dooley 2022-08-19 270 * setting a 100% duty cycle, as explained above. ae39414af22131 Conor Dooley 2022-08-19 271 * As the period is not locked, we are free to fix this. ae39414af22131 Conor Dooley 2022-08-19 272 */ ae39414af22131 Conor Dooley 2022-08-19 273 if (period_steps == MCHPCOREPWM_PERIOD_STEPS_MAX) { ae39414af22131 Conor Dooley 2022-08-19 274 period_steps -= 1; ae39414af22131 Conor Dooley 2022-08-19 275 mchp_core_pwm_apply_period(mchp_core_pwm, prescale, period_steps); ae39414af22131 Conor Dooley 2022-08-19 276 } ae39414af22131 Conor Dooley 2022-08-19 277 } ae39414af22131 Conor Dooley 2022-08-19 278 ae39414af22131 Conor Dooley 2022-08-19 279 duty_steps = mchp_core_pwm_calc_duty(chip, pwm, state, prescale, period_steps); ae39414af22131 Conor Dooley 2022-08-19 280 ae39414af22131 Conor Dooley 2022-08-19 281 /* ae39414af22131 Conor Dooley 2022-08-19 282 * Because the period is per channel, it is possible that the requested ae39414af22131 Conor Dooley 2022-08-19 283 * duty cycle is longer than the period, in which case cap it to the ae39414af22131 Conor Dooley 2022-08-19 284 * period, IOW a 100% duty cycle. ae39414af22131 Conor Dooley 2022-08-19 285 */ ae39414af22131 Conor Dooley 2022-08-19 286 if (duty_steps > period_steps) ae39414af22131 Conor Dooley 2022-08-19 287 duty_steps = period_steps + 1; ae39414af22131 Conor Dooley 2022-08-19 288 ae39414af22131 Conor Dooley 2022-08-19 289 mchp_core_pwm_apply_duty(chip, pwm, state, duty_steps, period_steps); ae39414af22131 Conor Dooley 2022-08-19 290 ae39414af22131 Conor Dooley 2022-08-19 291 mchp_core_pwm_enable(chip, pwm, true, state->period); ae39414af22131 Conor Dooley 2022-08-19 292 ae39414af22131 Conor Dooley 2022-08-19 293 mutex_unlock(&mchp_core_pwm->lock); ae39414af22131 Conor Dooley 2022-08-19 294 ae39414af22131 Conor Dooley 2022-08-19 @295 return 0; ae39414af22131 Conor Dooley 2022-08-19 296 } ae39414af22131 Conor Dooley 2022-08-19 297 -- 0-DAY CI Kernel Test Service https://01.org/lkp _______________________________________________ kbuild mailing list -- kbuild@lists.01.org To unsubscribe send an email to kbuild-le...@lists.01.org
