From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD69478F29; Fri, 24 Jan 2025 13:19:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737724780; cv=none; b=obFm8J/XFfOj9ufQLIZOfMs4RhMpWtcc99ec9/dDE3C4NOQbaWkRjUxUk96CnqTxVlFulchD2S3U2cwr9zKvu/MrjRdOad5P6w1YcPk+OFAhvVKr1ED64S3lDneD+JvL8X+3O1Bn6ZaONajo3vj+0u6Nrn2EwVQfy6GlYRZvhak= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737724780; c=relaxed/simple; bh=JOu4TI6erL4+9c/VJMPhYunm6by8dXTNzBQiZe6VjU4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=VO20lLfZ0WVtmAWe1H65Cnh99CzxqxTZqBSdSIBOI7IGOnAWHQKjq8p44r8NJJ9YOgzDjgPFBKCEqGguMXoFb0QBtb2VyphAEv1jAVQC3lfSINZyqFLuTvOGwF5nYdLyghvdpKo5/iEczasGmsb0jydXJaH5x6EljwdzBKMkK3E= ARC-Authentication-Results:i=1; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi, On 15/01/2025 16:17, Sakari Ailus wrote: > Moi, > > On Fri, Jan 10, 2025 at 11:14:07AM +0200, Tomi Valkeinen wrote: >> From: Jai Luthra >> >> On the I2C bus for remote clients (sensors), by default the watchdog >> timer expires in 1s. To allow for a quicker system bring-up time, TI >> recommends to speed it up to 50us [1]. >> >> [1]: Section 7.3.1.1 - https://www.ti.com/lit/gpn/ds90ub953-q1 >> >> Signed-off-by: Jai Luthra >> Signed-off-by: Tomi Valkeinen >> --- >> drivers/media/i2c/ds90ub953.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c >> index 99a4852b9381..6c36980e8beb 100644 >> --- a/drivers/media/i2c/ds90ub953.c >> +++ b/drivers/media/i2c/ds90ub953.c >> @@ -54,6 +54,10 @@ >> #define UB953_REG_CLKOUT_CTRL0 0x06 >> #define UB953_REG_CLKOUT_CTRL1 0x07 >> >> +#define UB953_REG_I2C_CONTROL2 0x0a >> +#define UB953_REG_I2C_CONTROL2_SDA_OUTPUT_SETUP_SHIFT 4 >> +#define UB953_REG_I2C_CONTROL2_BUS_SPEEDUP BIT(1) >> + >> #define UB953_REG_SCL_HIGH_TIME 0x0b >> #define UB953_REG_SCL_LOW_TIME 0x0c >> >> @@ -1320,6 +1324,13 @@ static int ub953_hw_init(struct ub953_data *priv) >> if (ret) >> return ret; >> >> + v = 0; >> + v |= 1 << UB953_REG_I2C_CONTROL2_SDA_OUTPUT_SETUP_SHIFT; > > BIT()? Or at least 1U <<< ...;. It's a three-bit field, the value just happens to be 1. What's wrong with 1 << SHIFT? > >> + v |= UB953_REG_I2C_CONTROL2_BUS_SPEEDUP; >> + ret = ub953_write(priv, UB953_REG_I2C_CONTROL2, v, NULL); > > I'd just do this without a temporary variable. If you prefer to keep it, do > assign the first calculated value there first and remove the assignment to > zero. I think we can do without. >> + if (ret) >> + return ret; > > No need for this. No, but it keeps the code structure consistent and allows easy future/debug modifications. Tomi