From: Stephen Boyd <sboyd@kernel.org>
To: Claudiu Beznea <claudiu.beznea@microchip.com>,
alexandre.belloni@bootlin.com, ludovic.desroches@microchip.com,
mturquette@baylibre.com, nicolas.ferre@microchip.com
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>,
linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/4] clk: at91: usb: continue if clk_hw_round_rate() return zero
Date: Wed, 12 Feb 2020 15:32:03 -0800 [thread overview]
Message-ID: <158155032378.184098.13418432475305981955@swboyd.mtv.corp.google.com> (raw)
In-Reply-To: <1579261009-4573-2-git-send-email-claudiu.beznea@microchip.com>
Quoting Claudiu Beznea (2020-01-17 03:36:46)
> clk_hw_round_rate() may call round rate function of its parents. In case
> of SAM9X60 two of USB parrents are PLLA and UPLL. These clocks are
> controlled by clk-sam9x60-pll.c driver. The round rate function for this
> driver is sam9x60_pll_round_rate() which call in turn
> sam9x60_pll_get_best_div_mul(). In case the requested rate is not in the
> proper range (rate < characteristics->output[0].min &&
> rate > characteristics->output[0].max) the sam9x60_pll_round_rate() will
> return a negative number to its caller (called by
> clk_core_round_rate_nolock()). clk_hw_round_rate() will return zero in
> case a negative number is returned by clk_core_round_rate_nolock(). With
> this, the USB clock will continue its rate computation even caller of
> clk_hw_round_rate() returned an error. With this, the USB clock on SAM9X60
> may not chose the best parent. I detected this after a suspend/resume
> cycle on SAM9X60.
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> ---
Applied to clk-next
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-02-12 23:32 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-17 11:36 [PATCH 0/4] clock fixes for at91 Claudiu Beznea
2020-01-17 11:36 ` [PATCH 1/4] clk: at91: usb: continue if clk_hw_round_rate() return zero Claudiu Beznea
2020-02-12 23:32 ` Stephen Boyd [this message]
2020-01-17 11:36 ` [PATCH 2/4] clk: at91: sam9x60: fix usb clock parents Claudiu Beznea
2020-01-17 21:28 ` Alexandre Belloni
2020-02-12 23:32 ` Stephen Boyd
2020-01-17 11:36 ` [PATCH 3/4] clk: at91: usb: use proper usbs_mask Claudiu Beznea
2020-01-17 21:28 ` Alexandre Belloni
2020-02-12 23:32 ` Stephen Boyd
2020-01-17 11:36 ` [PATCH 4/4] clk: at91: usb: introduce num_parents in driver's structure Claudiu Beznea
2020-01-17 21:29 ` Alexandre Belloni
2020-02-12 23:32 ` Stephen Boyd
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=158155032378.184098.13418432475305981955@swboyd.mtv.corp.google.com \
--to=sboyd@kernel.org \
--cc=alexandre.belloni@bootlin.com \
--cc=claudiu.beznea@microchip.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=ludovic.desroches@microchip.com \
--cc=mturquette@baylibre.com \
--cc=nicolas.ferre@microchip.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).