| Message ID | 1370324564.26072.22.camel@younglee-desktop (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 4 Jun 2013 13:42:44 +0800 lbyang <lbyang@marvell.com> wrote: > +static void mcam_clk_enable(struct mcam_camera *mcam) > +{ > + unsigned int i; > + > + for (i = 0; i < NR_MCAM_CLK; i++) { > + if (!IS_ERR_OR_NULL(mcam->clk[i])) > + clk_prepare_enable(mcam->clk[i]); > + } > +} It seems I already acked this patch, and I won't take that back. I will point out, though, that IS_ERR_OR_NULL has become a sort of lightning rod and that its use is probably best avoided. http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/140543.html This relates to the use of ERR_PTR with that particular pointer value; I still think just using NULL is better, but maybe I'm missing something. jon -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Jonathan, Do you mean using IS_ERR() here directly? I think it should be OK. I will change to IS_ERR() in next version. Regards, Libin >-----Original Message----- >From: Jonathan Corbet [mailto:corbet@lwn.net] >Sent: Saturday, June 22, 2013 1:02 AM >To: Libin Yang >Cc: g.liakhovetski@gmx.de; mchehab@redhat.com; >linux-media@vger.kernel.org; albert.v.wang@gmail.com >Subject: Re: [PATCH 2/7] marvell-ccic: add clock tree support >for marvell-ccic driver > >On Tue, 4 Jun 2013 13:42:44 +0800 >lbyang <lbyang@marvell.com> wrote: > >> +static void mcam_clk_enable(struct mcam_camera *mcam) { >> + unsigned int i; >> + >> + for (i = 0; i < NR_MCAM_CLK; i++) { >> + if (!IS_ERR_OR_NULL(mcam->clk[i])) >> + clk_prepare_enable(mcam->clk[i]); >> + } >> +} > >It seems I already acked this patch, and I won't take that >back. I will point out, though, that IS_ERR_OR_NULL has >become a sort of lightning rod and that its use is probably >best avoided. > > >http://lists.infradead.org/pipermail/linux-arm-kernel/2013-Janu >ary/140543.html > >This relates to the use of ERR_PTR with that particular >pointer value; I still think just using NULL is better, but >maybe I'm missing something. > >jon >-- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/media/platform/marvell-ccic/mcam-core.h b/drivers/media/platform/marvell-ccic/mcam-core.h index be271b3..c506cd3 100644 --- a/drivers/media/platform/marvell-ccic/mcam-core.h +++ b/drivers/media/platform/marvell-ccic/mcam-core.h @@ -83,6 +83,8 @@ struct mcam_frame_state { unsigned int delivered; }; +#define NR_MCAM_CLK 3 + /* * A description of one of our devices. * Locking: controlled by s_mutex. Certain fields, however, require @@ -113,6 +115,9 @@ struct mcam_camera { bool mipi_enabled; int lane; /* lane number */ + /* clock tree support */ + struct clk *clk[NR_MCAM_CLK]; + /* * Callbacks from the core to the platform code. */ diff --git a/drivers/media/platform/marvell-ccic/mmp-driver.c b/drivers/media/platform/marvell-ccic/mmp-driver.c index 3dad182..233d0ff 100644 --- a/drivers/media/platform/marvell-ccic/mmp-driver.c +++ b/drivers/media/platform/marvell-ccic/mmp-driver.c @@ -35,6 +35,8 @@ MODULE_ALIAS("platform:mmp-camera"); MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>"); MODULE_LICENSE("GPL"); +static char *mcam_clks[] = {"CCICAXICLK", "CCICFUNCLK", "CCICPHYCLK"}; + struct mmp_camera { void *power_regs; struct platform_device *pdev; @@ -105,6 +107,26 @@ static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev) #define REG_CCIC_DCGCR 0x28 /* CCIC dyn clock gate ctrl reg */ #define REG_CCIC_CRCR 0x50 /* CCIC clk reset ctrl reg */ +static void mcam_clk_enable(struct mcam_camera *mcam) +{ + unsigned int i; + + for (i = 0; i < NR_MCAM_CLK; i++) { + if (!IS_ERR_OR_NULL(mcam->clk[i])) + clk_prepare_enable(mcam->clk[i]); + } +} + +static void mcam_clk_disable(struct mcam_camera *mcam) +{ + int i; + + for (i = NR_MCAM_CLK - 1; i >= 0; i--) { + if (!IS_ERR_OR_NULL(mcam->clk[i])) + clk_disable_unprepare(mcam->clk[i]); + } +} + /* * Power control. */ @@ -135,11 +157,15 @@ static int mmpcam_power_up(struct mcam_camera *mcam) mdelay(5); gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */ mdelay(5); + + mcam_clk_enable(mcam); + if (mcam->bus_type == V4L2_MBUS_CSI2 && IS_ERR(cam->mipi_clk)) { cam->mipi_clk = devm_clk_get(mcam->dev, "mipi"); if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0)) return PTR_ERR(cam->mipi_clk); } + return 0; } @@ -163,6 +189,8 @@ static void mmpcam_power_down(struct mcam_camera *mcam) devm_clk_put(mcam->dev, cam->mipi_clk); cam->mipi_clk = ERR_PTR(-EINVAL); } + + mcam_clk_disable(mcam); } /* @@ -271,6 +299,23 @@ static irqreturn_t mmpcam_irq(int irq, void *data) return IRQ_RETVAL(handled); } +static int mcam_init_clk(struct mcam_camera *mcam, + struct mmp_camera_platform_data *pdata) +{ + unsigned int i; + + for (i = 0; i < NR_MCAM_CLK; i++) { + if (mcam_clks[i] != NULL) { + mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]); + if (IS_ERR(mcam->clk[i])) { + dev_err(mcam->dev, "Could not get clk: %s\n", + mcam_clks[i]); + return PTR_ERR(mcam->clk[i]); + } + } + } + return 0; +} static int mmpcam_probe(struct platform_device *pdev) { @@ -338,6 +383,9 @@ static int mmpcam_probe(struct platform_device *pdev) ret = -ENODEV; goto out_unmap1; } + + mcam_init_clk(mcam, pdata); + /* * Find the i2c adapter. This assumes, of course, that the * i2c bus is already up and functioning.