Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752009AbbEZUFZ (ORCPT ); Tue, 26 May 2015 16:05:25 -0400 Received: from mail-gw2-out.broadcom.com ([216.31.210.63]:30842 "EHLO mail-gw2-out.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751808AbbEZUFV (ORCPT ); Tue, 26 May 2015 16:05:21 -0400 X-IronPort-AV: E=Sophos;i="5.13,501,1427785200"; d="scan'208";a="65847136" From: Jonathan Richardson To: Tim Kryger , Dmitry Torokhov , Anatol Pomazau , Arun Ramamurthy , Thierry Reding CC: Scott Branden , Jonathan Richardson , bcm-kernel-feedback-list , , Subject: [PATCH v8 4/5] pwm: kona: Add debug info to config function Date: Tue, 26 May 2015 13:08:19 -0700 Message-ID: <1432670900-27687-5-git-send-email-jonathar@broadcom.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1432670900-27687-1-git-send-email-jonathar@broadcom.com> References: <1432670900-27687-1-git-send-email-jonathar@broadcom.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2126 Lines: 62 Adds debugging info to config function where duty cycle and period are calculated and verified. Signed-off-by: Jonathan Richardson --- drivers/pwm/pwm-bcm-kona.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-bcm-kona.c b/drivers/pwm/pwm-bcm-kona.c index c87621f..0ddf19b 100644 --- a/drivers/pwm/pwm-bcm-kona.c +++ b/drivers/pwm/pwm-bcm-kona.c @@ -138,18 +138,39 @@ static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm, dc = div64_u64(val, div); /* If duty_ns or period_ns are not achievable then return */ - if (pc < PERIOD_COUNT_MIN || dc < DUTY_CYCLE_HIGH_MIN) + if (pc < PERIOD_COUNT_MIN) { + dev_warn(chip->dev, + "%s: pwm[%d]: period=%d is not achievable, pc=%lu, prescale=%lu\n", + __func__, chan, period_ns, pc, prescale); return -EINVAL; + } + + if (dc < DUTY_CYCLE_HIGH_MIN) { + if (0 != duty_ns) { + dev_warn(chip->dev, + "%s: pwm[%d]: duty cycle=%d is not achievable, dc=%lu, prescale=%lu\n", + __func__, chan, duty_ns, dc, prescale); + } + return -EINVAL; + } /* If pc and dc are in bounds, the calculation is done */ if (pc <= PERIOD_COUNT_MAX && dc <= DUTY_CYCLE_HIGH_MAX) break; /* Otherwise, increase prescale and recalculate pc and dc */ - if (++prescale > PRESCALE_MAX) + if (++prescale > PRESCALE_MAX) { + dev_warn(chip->dev, + "%s: pwm[%d]: Prescale (=%lu) within max (=%d) for period=%d and duty cycle=%d is not achievable\n", + __func__, chan, prescale, PRESCALE_MAX, + period_ns, duty_ns); return -EINVAL; + } } + dev_dbg(chip->dev, "pwm[%d]: period=%lu, duty_high=%lu, prescale=%lu\n", + chan, pc, dc, prescale); + /* * Don't apply settings if disabled. The period and duty cycle are * always calculated above to ensure the new values are -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/