From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794063802; b=xPeE2hPOUFtnpqgrITP9g/aQqgACO4/rEeCPO/0jxhbH15hYqGynD1QwO4ukzA9Ar7xn 2FHI5bV0ywtLsIk2gqIZ+yHFhVUhwvodDQx05IBcygLEOxVJEDZ5yjJPtgWIvgAfRJ2uT 5iqD4tZ9xv34v3R2OesFwa0yW0Z4607KwPVPoWsQf5P5p42NDkPBuXJCcBupkOuoLwY2f QTh4kGAtZVv9L0ChE05vlI+8OzoH/uSYnlERnFrxQPjKoHuoGujXnGYGZwc0/kJh+xhK2 Mpkx9nSySii9a1Cof/BdSqi4exCJteEnf5eMOALcB/M1IDV7iLNsNNEua1aEWb9ooMQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063802; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=+vKnj/Y0N/xnZIYxsbTdbP/tEEKWX6hGWB+SqfdejuM=; b=M4NZ7JOb3rmN6sd81CS2lRNrmOO4yXkKcwq82d9024Bp6gt/jedvgT8bEnh4m3OUDCXE b2ZEr6vK/vUStPlWHz4TWpXiMtEXad1EDA18xPZDmqBXYfStMNRZlJawpWsV8/ruJZ1d6 nSsgFyb8LBsUkHK6P3Jncp1PLmVpYj+QSyqLP32MJxmcSTbkqRJ0DCPpHXBcfcJIL6Uf5 zAOE9k+ZwsriqIMOaGOKkfX4GQGlReYVTtIcpZAF42fgWdyeEhYr/IyMgUARnaROzqZyq wyOzU2nOqEML5PPNXYk7GJj/y6T8FvfJhLAYvVuUti8qpg0eAWR5+ZeCAQlPcgYApZQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b="V/GLXvrx"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 01899606EE81; Sat, 7 Nov 2026 15:03:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=V/GLXvrx Received: by smtp.kernel.org (Postfix) with ESMTPSA id A39021F0089F; Sat, 7 Nov 2026 15:03:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063801; bh=+vKnj/Y0N/xnZIYxsbTdbP/tEEKWX6hGWB+SqfdejuM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=V/GLXvrxugmseJtSoQf3cgLttRajoiM0n0J4e615SQEtqdt7z7aqx+pCYWOEnS4CW e8+iBgy5yvkufos7jt/sB5HAJVWDdhKPRrNI12P8cceMfl44QibpwJ2yOIr+NDzYN9 Xjld5nD/I1P21mmHys/ErY9Cud1h5xkd0FIhtnuQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jakub Szczudlo , Andy Shevchenko , Stable@vger.kernel.org, Jonathan Cameron , Sasha Levin Subject: [PATCH 7.3 0022/1257] iio: adc: ti-ads1100: Fix incorrect reading when datarate changed in single mode Date: Sat, 7 Nov 2026 08:38:38 -0500 Message-ID: <20261107134940.025637593@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Szczudlo [ Upstream commit 38dbf24dfbd0a73b89fa2871a7148429aef05531 ] When device is suspended and it is in single mode then changing datarate doesn't make it actually wait for new measurement, so to be sure that read after change is correct, functions that changes datarate and gain will wait for a new data. Fixes: 541880542f2b ("iio: adc: Add TI ADS1100 and ADS1000") Signed-off-by: Jakub Szczudlo Reviewed-by: Andy Shevchenko Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/adc/ti-ads1100.c | 107 +++++++++++++++++++++++++++++++++-- 1 file changed, 103 insertions(+), 4 deletions(-) diff --git a/drivers/iio/adc/ti-ads1100.c b/drivers/iio/adc/ti-ads1100.c index 9fe8d54cce83c..03096d7e10914 100644 --- a/drivers/iio/adc/ti-ads1100.c +++ b/drivers/iio/adc/ti-ads1100.c @@ -15,10 +15,12 @@ #include #include #include +#include #include #include #include #include +#include #include #include @@ -43,6 +45,9 @@ static const int ads1100_data_rate[] = { 128, 32, 16, 8 }; static const int ads1100_data_rate_bits[] = { 12, 14, 15, 16 }; +/* Timeout based on the minimum sample rate of 8 SPS (7500ms) */ +#define ADS1100_MAX_DRDY_TIMEOUT_US (7500 * USEC_PER_MSEC) + struct ads1100_data { struct i2c_client *client; struct regulator *reg_vdd; @@ -123,10 +128,86 @@ static int ads1100_get_adc_result(struct ads1100_data *data, int chan, int *val) return 0; } +static int ads1100_conversion_busy(struct ads1100_data *data) +{ + u8 buffer[3]; + int ret; + + ret = i2c_master_recv(data->client, (char *)&buffer, sizeof(buffer)); + if (ret < 0) { + dev_err(&data->client->dev, "I2C read fail: %d\n", ret); + return ret; + } + + return FIELD_GET(ADS1100_CFG_ST_BSY, buffer[2]); +} + +static int ads1100_wait_single_conversion(struct ads1100_data *data) +{ + int data_rate_index = FIELD_GET(ADS1100_DR_MASK, data->config); + int data_rate_Hz = ads1100_data_rate[data_rate_index]; + unsigned long poll_us = DIV_ROUND_CLOSEST(USEC_PER_SEC, data_rate_Hz) / 4; + int busy; + int ret; + + ret = readx_poll_timeout(ads1100_conversion_busy, data, + busy, busy <= 0, + poll_us, ADS1100_MAX_DRDY_TIMEOUT_US); + if (busy < 0) + return busy; + + return ret; +} + +static int ads1100_start_single_conversion(struct ads1100_data *data) +{ + u8 config = data->config | ADS1100_CFG_SC; + int ret; + + ret = i2c_master_send(data->client, &config, sizeof(config)); + if (ret < 0) { + dev_err(&data->client->dev, "I2C write fail: %d\n", ret); + return ret; + } + /* Need to wait because of change from continuous to single mode */ + ret = ads1100_wait_single_conversion(data); + if (ret) + return ret; + + config |= ADS1100_CFG_ST_BSY; + + ret = i2c_master_send(data->client, &config, sizeof(config)); + if (ret < 0) { + dev_err(&data->client->dev, "I2C write fail: %d\n", ret); + return ret; + } + + /* No need to cache it, it's status bit */ + data->config = config & ~ADS1100_CFG_ST_BSY; + + return 0; +} + +static int ads1100_poll_data_ready(struct ads1100_data *data) +{ + int ret; + + ret = ads1100_start_single_conversion(data); + if (ret) + return ret; + + ret = ads1100_wait_single_conversion(data); + if (ret) + return ret; + + return ads1100_set_config_bits(data, ADS1100_CFG_SC, ADS1100_CONTINUOUS); +} + static int ads1100_set_scale(struct ads1100_data *data, int val, int val2) { int microvolts; int gain; + int ret; /* With Vdd between 2.7 and 5V, the scale is always below 1 */ if (val) @@ -135,6 +216,11 @@ static int ads1100_set_scale(struct ads1100_data *data, int val, int val2) if (!val2) return -EINVAL; + PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(&data->client->dev, pm); + ret = PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; + microvolts = regulator_get_voltage(data->reg_vdd); /* * val2 is in 'micro' units, n = val2 / 1000000 @@ -149,22 +235,35 @@ static int ads1100_set_scale(struct ads1100_data *data, int val, int val2) ads1100_set_config_bits(data, ADS1100_PGA_MASK, ffs(gain) - 1); - return 0; + return ads1100_poll_data_ready(data); } static int ads1100_set_data_rate(struct ads1100_data *data, int chan, int rate) { unsigned int i; unsigned int size; + int ret; size = data->supports_data_rate ? ARRAY_SIZE(ads1100_data_rate) : 1; for (i = 0; i < size; i++) { if (ads1100_data_rate[i] == rate) - return ads1100_set_config_bits(data, ADS1100_DR_MASK, - FIELD_PREP(ADS1100_DR_MASK, i)); + break; } - return -EINVAL; + if (i == size) + return -EINVAL; + + PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND(&data->client->dev, pm); + ret = PM_RUNTIME_ACQUIRE_ERR(&pm); + if (ret) + return ret; + + ret = ads1100_set_config_bits(data, ADS1100_DR_MASK, + FIELD_PREP(ADS1100_DR_MASK, i)); + if (ret) + return ret; + + return ads1100_poll_data_ready(data); } static int ads1100_get_vdd_millivolts(struct ads1100_data *data) -- 2.53.0