From: Tony Lindgren <tony@atomide.com>
To: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>, Tero Kristo <t-kristo@ti.com>,
linux-omap@vger.kernel.org, nm@ti.com,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 01/23] ARM: OMAP2+: clock: move clock provider infrastructure to clock driver
Date: Tue, 27 Jan 2015 08:50:16 -0800 [thread overview]
Message-ID: <20150127165016.GJ28663@atomide.com> (raw)
In-Reply-To: <54C777CE.1070900@ti.com>
* Tomi Valkeinen <tomi.valkeinen@ti.com> [150127 03:37]:
> On 26/01/15 17:49, Tony Lindgren wrote:
>
> >> I'm not sure if I miss something, but regmap_write does not protect from
> >> problems if there are multiple users for the same registers. You need to
> >> use regmap_update_bits() to get a protected read/write sequence, in
> >> which you can change only the bits that you want to change.
> >
> > To me it seems that issue can be fixed by making all the code use regmap.
> > AFAIK that should work for the legacy code too.
>
> Even if everybody uses regmap, doing
>
> v = regmap_read()
> modify v
> regmap_write(v)
>
> is racy. regmap_update_bits() has to be used to protect the read/write
> sequence. Which may be somewhat challenging at times with some strange
> registers, the like Roger Q encountered recently related to CAN.
Yeah that's a good point.
Regards,
Tony
next prev parent reply other threads:[~2015-01-27 16:53 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-27 15:51 [PATCH 00/23] ARM: OMAP2+: PRCM cleanups towards 3.19 / part2 Tero Kristo
2014-11-27 15:51 ` [PATCH 01/23] ARM: OMAP2+: clock: move clock provider infrastructure to clock driver Tero Kristo
2015-01-24 21:51 ` Paul Walmsley
2015-01-26 10:38 ` Tomi Valkeinen
2015-01-26 15:49 ` Tony Lindgren
2015-01-27 11:34 ` Tomi Valkeinen
2015-01-27 16:50 ` Tony Lindgren [this message]
2015-02-13 15:06 ` Tero Kristo
2014-11-27 15:51 ` [PATCH 02/23] ARM: OMAP2+: PRCM: rename of_prcm_init to omap_prcm_init Tero Kristo
2014-11-27 15:51 ` [PATCH 03/23] ARM: OMAP2+: PRCM: split PRCM module init to their own driver files Tero Kristo
2014-11-27 15:51 ` [PATCH 04/23] ARM: OMAP24xx: clock: remove unused apll code Tero Kristo
2015-01-07 19:06 ` Tony Lindgren
2014-11-27 15:51 ` [PATCH 05/23] ARM: OMAP2: CM: remove unused PLL functions Tero Kristo
2015-01-07 19:06 ` Tony Lindgren
2014-11-27 15:51 ` [PATCH 06/23] ARM: OMAP3: PRM: invert the wkst_mask for the prm_clear_mod_irqs Tero Kristo
2014-11-27 15:51 ` [PATCH 07/23] ARM: OMAP2+: PRM: add generic API for clear_mod_irqs Tero Kristo
2014-11-27 15:51 ` [PATCH 08/23] ARM: OMAP3+: PRM: remove prm_get_reset_sources declaration from headers Tero Kristo
2015-01-07 19:06 ` Tony Lindgren
2014-11-27 15:51 ` [PATCH 09/23] ARM: OMAP3+: PRM: add common APIs for prm_vp_check/clear_txdone Tero Kristo
2014-11-27 15:51 ` [PATCH 10/23] ARM: OMAP4+: PRM: move omap_prm_base_init under OMAP4 PRM driver Tero Kristo
2014-11-27 15:51 ` [PATCH 11/23] ARM: OMAP4+: CM: move omap_cm_base_init under OMAP4 CM driver Tero Kristo
2014-11-27 15:51 ` [PATCH 12/23] ARM: OMAP2+: clock: add support for static clock memmap indexes Tero Kristo
2014-11-27 15:51 ` [PATCH 13/23] ARM: OMAP2+: CM: determine CM base address from device tree Tero Kristo
2015-01-24 19:39 ` Paul Walmsley
2015-02-13 15:07 ` Tero Kristo
2014-11-27 15:51 ` [PATCH 14/23] ARM: OMAP4: PRM: move omap4xxx_prm_init earlier in init order Tero Kristo
2014-11-27 15:51 ` [PATCH 15/23] ARM: OMAP2+: PRM: determine PRM base address from device tree Tero Kristo
2014-11-27 15:51 ` [PATCH 16/23] ARM: OMAP4: omapdss: remove legacy pad muxing support Tero Kristo
2014-11-27 16:09 ` Tomi Valkeinen
2014-11-28 7:58 ` Tero Kristo
2015-01-24 20:06 ` Paul Walmsley
2014-11-27 15:51 ` [PATCH 17/23] ARM: OMAP4: control: remove support for legacy padconf APIs Tero Kristo
2015-01-24 20:06 ` Paul Walmsley
2014-11-27 15:51 ` [PATCH 18/23] ARM: OMAP2+: control: determine control module base address from DT Tero Kristo
2014-11-27 15:51 ` [PATCH 19/23] ARM: OMAP2+: PRM: move SoC specific init calls within a generic API Tero Kristo
2014-11-27 15:51 ` [PATCH 20/23] ARM: OMAP4+: PRM: determine prm_device_inst based on DT compatibility Tero Kristo
2014-11-27 15:51 ` [PATCH 21/23] ARM: OMAP2+: CM: move SoC specific init calls within a generic API Tero Kristo
2014-11-27 15:51 ` [PATCH 22/23] ARM: OMAP4+: PRM: setup prm_features from the PRM init time flags Tero Kristo
2014-11-27 15:51 ` [PATCH 23/23] ARM: OMAP4+: PRM: get rid of cpu_is_omap44xx calls from interrupt init Tero Kristo
2014-11-27 19:15 ` [PATCH 00/23] ARM: OMAP2+: PRCM cleanups towards 3.19 / part2 Paul Walmsley
2014-12-01 15:58 ` Tero Kristo
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