2017-11-06 10:29:50

by Simon Shields

[permalink] [raw]
Subject: Re: [PATCH] brcmfmac: add support for external 32khz clock

Some boards use an external 32khz clock for low-power
mode timing. Make sure the clock is powered on while the chipset
is active.

Signed-off-by: Simon Shields <[email protected]>
---
.../devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt | 2 ++
drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h | 2 ++
drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c | 5 +++++
drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 10 ++++++++++
4 files changed, 19 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt b/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt
index b2bd4704f859..37add5e29272 100644
--- a/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt
+++ b/Documentation/devicetree/bindings/net/wireless/brcm,bcm43xx-fmac.txt
@@ -17,6 +17,8 @@ Optional properties:
When not specified the device will use in-band SDIO interrupts.
- interrupt-names : name of the out-of-band interrupt, which must be set
to "host-wake".
+ - clocks : external 32khz clock
+ - clock-names : name of the external 32khz clock, must be "32khz"

Example:

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
index a62f8e70b320..2e7fabae81d3 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
@@ -51,6 +51,7 @@ extern struct brcmf_mp_global_t brcmf_mp_global;
* @roamoff: Firmware roaming off?
* @ignore_probe_fail: Ignore probe failure.
* @country_codes: If available, pointer to struct for translating country codes
+ * @clk: External 32khz clock, if present.
* @bus: Bus specific platform data. Only SDIO at the mmoment.
*/
struct brcmf_mp_device {
@@ -60,6 +61,7 @@ struct brcmf_mp_device {
bool roamoff;
bool ignore_probe_fail;
struct brcmfmac_pd_cc *country_codes;
+ struct clk *clk;
union {
struct brcmfmac_sdio_pd sdio;
} bus;
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
index aee6e5937c41..46f42a2c3d2b 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
@@ -13,6 +13,7 @@
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
+#include <linux/clk.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_irq.h>
@@ -39,6 +40,10 @@ void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
if (of_property_read_u32(np, "brcm,drive-strength", &val) == 0)
sdio->drive_strength = val;

+ settings->clk = devm_clk_get(dev, "32khz");
+ if (IS_ERR(settings->clk))
+ settings->clk = NULL;
+
/* make sure there are interrupts defined in the node */
if (!of_find_property(np, "interrupts", NULL))
return;
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
index 613caca7dc02..f4ceca6dbe74 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
@@ -14,6 +14,7 @@
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

+#include <linux/clk.h>
#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/kernel.h>
@@ -3853,6 +3854,11 @@ brcmf_sdio_probe_attach(struct brcmf_sdio *bus)
brcmf_err("Failed to get device parameters\n");
goto fail;
}
+
+ /* enable external 32khz clock, if present */
+ if (sdiodev->settings->clk)
+ clk_prepare_enable(sdiodev->settings->clk);
+
/* platform specific configuration:
* alignments must be at least 4 bytes for ADMA
*/
@@ -4270,6 +4276,10 @@ void brcmf_sdio_remove(struct brcmf_sdio *bus)
}
brcmf_chip_detach(bus->ci);
}
+
+ if (bus->sdiodev->settings->clk)
+ clk_disable_unprepare(bus->sdiodev->settings->clk);
+
if (bus->sdiodev->settings)
brcmf_release_module_param(bus->sdiodev->settings);

--
2.15.0


2017-11-06 10:43:51

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH] brcmfmac: add support for external 32khz clock

Simon Shields <[email protected]> writes:

> Some boards use an external 32khz clock for low-power
> mode timing. Make sure the clock is powered on while the chipset
> is active.
>
> Signed-off-by: Simon Shields <[email protected]>

Then you submit a new version please always increase the version so that
I know which patch I should follow and take from patchwork:

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches#patch_version_missing

And yes yes, I know the patch content was identical in this case but
even a change in Cc field is important from my point of view. No need to
resend, this reply is also a reminder to me that this is the v2 :)

--
Kalle Valo