From patchwork Tue Jan 3 12:27:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jai Luthra X-Patchwork-Id: 638964 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5307C46467 for ; Tue, 3 Jan 2023 12:28:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237470AbjACM2E (ORCPT ); Tue, 3 Jan 2023 07:28:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237468AbjACM1w (ORCPT ); Tue, 3 Jan 2023 07:27:52 -0500 Received: from lelv0143.ext.ti.com (lelv0143.ext.ti.com [198.47.23.248]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C12ADC29 for ; Tue, 3 Jan 2023 04:27:50 -0800 (PST) Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id 303CRhXq089422; Tue, 3 Jan 2023 06:27:43 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1672748863; bh=8nzV68I9fpNjSA3LbuRKemksL4nN7yUw6c9KIVIdZQ8=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=JpVSD7u8d/C40iOxsu3i8R02hA4uBsazNPkBtAOyEUfSEPmb7KfeutcDcKnUIoO4w 4Rtdx4bpqC+k53AkbPhR+g9s4rZPFwyXcQSEf5RMAAbHqMGUt3yk5XhpckZS/YYM9r mzA71/2byeQ39Hg7O0DoVDQ099LOc5XCJX/xNBZw= Received: from DFLE100.ent.ti.com (dfle100.ent.ti.com [10.64.6.21]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 303CRhTZ065716 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 3 Jan 2023 06:27:43 -0600 Received: from DFLE108.ent.ti.com (10.64.6.29) by DFLE100.ent.ti.com (10.64.6.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.16; Tue, 3 Jan 2023 06:27:42 -0600 Received: from fllv0039.itg.ti.com (10.64.41.19) by DFLE108.ent.ti.com (10.64.6.29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.16 via Frontend Transport; Tue, 3 Jan 2023 06:27:43 -0600 Received: from localhost (ileaxei01-snat.itg.ti.com [10.180.69.5]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 303CRgXw102479; Tue, 3 Jan 2023 06:27:42 -0600 From: Jai Luthra To: Steve Longerbeam , Mauro Carvalho Chehab , Sakari Ailus , Jacopo Mondi CC: , Nishanth Menon , Jai Luthra Subject: [PATCH v4 2/2] media: ov5640: Handle delays when no reset_gpio set Date: Tue, 3 Jan 2023 17:57:36 +0530 Message-ID: <20230103122736.18479-3-j-luthra@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230103122736.18479-1-j-luthra@ti.com> References: <20230103122736.18479-1-j-luthra@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Some module manufacturers [1][2] don't expose the RESETB and PWDN pins of the sensor directly through the 15-pin FFC connector. Instead wiring ~PWDN gpio to the sensor pins with appropriate delays. In such cases, reset_gpio will not be available to the driver, but it will still be toggled when the sensor is powered on, and thus we should still honor the wait time of >= 5ms + 1ms + 20ms (see figure 2-3 in [3]) before attempting any i/o operations over SCCB. Also, rename the function to ov5640_powerup_sequence to better match the datasheet (section 2.7). [1] https://digilent.com/reference/_media/reference/add-ons/pcam-5c/pcam_5c_sch.pdf [2] https://www.alinx.com/public/upload/file/AN5641_User_Manual.pdf [3] https://cdn.sparkfun.com/datasheets/Sensors/LightImaging/OV5640_datasheet.pdf Fixes: 19a81c1426c1 ("[media] add Omnivision OV5640 sensor driver") Reported-by: Nishanth Menon Signed-off-by: Jai Luthra Reviewed-by: Jacopo Mondi --- drivers/media/i2c/ov5640.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c index 9f3913aad93c..5fba473132e5 100644 --- a/drivers/media/i2c/ov5640.c +++ b/drivers/media/i2c/ov5640.c @@ -2425,11 +2425,22 @@ static void ov5640_power(struct ov5640_dev *sensor, bool enable) gpiod_set_value_cansleep(sensor->pwdn_gpio, enable ? 0 : 1); } -static void ov5640_reset(struct ov5640_dev *sensor) +/* + * From section 2.7 power up sequence: + * t0 + t1 + t2 >= 5ms Delay from DOVDD stable to PWDN pull down + * t3 >= 1ms Delay from PWDN pull down to RESETB pull up + * t4 >= 20ms Delay from RESETB pull up to SCCB (i2c) stable + * + * Some modules don't expose RESETB/PWDN pins directly, instead providing a + * "PWUP" GPIO which is wired through appropriate delays and inverters to the + * pins. + * + * In such cases, this gpio should be mapped to pwdn_gpio in the driver, and we + * should still toggle the pwdn_gpio below with the appropriate delays, while + * the calls to reset_gpio will be ignored. + */ +static void ov5640_powerup_sequence(struct ov5640_dev *sensor) { - if (!sensor->reset_gpio) - return; - if (sensor->pwdn_gpio) { gpiod_set_value_cansleep(sensor->reset_gpio, 0); @@ -2477,8 +2488,7 @@ static int ov5640_set_power_on(struct ov5640_dev *sensor) goto xclk_off; } - ov5640_reset(sensor); - ov5640_power(sensor, true); + ov5640_powerup_sequence(sensor); ret = ov5640_init_slave_id(sensor); if (ret)