From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicolas.ferre@atmel.com (Nicolas Ferre) Date: Tue, 16 Jul 2013 10:46:28 +0200 Subject: [PATCH 2/5] iio: at91: Use different prescal, startup mask in MR for different IP In-Reply-To: <51E505EA.4060502@atmel.com> References: <1373789069-11604-1-git-send-email-josh.wu@atmel.com> <1373789069-11604-3-git-send-email-josh.wu@atmel.com> <20130715125815.GC2962@lukather> <51E505EA.4060502@atmel.com> Message-ID: <51E50864.6020904@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 16/07/2013 10:35, Josh Wu : > Hi, Maxime > > On 7/15/2013 8:58 PM, Maxime Ripard wrote: >> Hi Josh, >> >> On Sun, Jul 14, 2013 at 04:04:26PM +0800, Josh Wu wrote: >>> For at91 boards, there are different IPs for adc. Different IPs has >>> different >>> STARTUP & PRESCAL mask in ADC_MR. >>> >>> This patch can change the masks according to the different IP version. >>> >>> Signed-off-by: Josh Wu >>> --- >>> arch/arm/mach-at91/include/mach/at91_adc.h | 9 ++++-- >>> drivers/iio/adc/at91_adc.c | 48 >>> ++++++++++++++++++++++++++-- >>> 2 files changed, 53 insertions(+), 4 deletions(-) >>> >>> diff --git a/arch/arm/mach-at91/include/mach/at91_adc.h >>> b/arch/arm/mach-at91/include/mach/at91_adc.h >>> index 8e7ed5c..ab273ee 100644 >>> --- a/arch/arm/mach-at91/include/mach/at91_adc.h >>> +++ b/arch/arm/mach-at91/include/mach/at91_adc.h >>> @@ -28,9 +28,12 @@ >>> #define AT91_ADC_TRGSEL_EXTERNAL (6 << 1) >>> #define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */ >>> #define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */ >>> -#define AT91_ADC_PRESCAL (0x3f << 8) /* Prescalar Rate >>> Selection */ >>> +#define AT91_ADC_PRESCAL (0xff << 8) /* Prescalar Rate >>> Selection */ >>> +#define AT91_ADC_PRESCAL_9260 (0x3f << 8) >>> #define AT91_ADC_PRESCAL_(x) ((x) << 8) >>> -#define AT91_ADC_STARTUP (0x1f << 16) /* Startup Up >>> Time */ >>> +#define AT91_ADC_STARTUP (0xf << 16) /* Startup Up Time */ >>> +#define AT91_ADC_STARTUP_9260 (0x1f << 16) >>> +#define AT91_ADC_STARTUP_9G45 (0x7f << 16) >>> #define AT91_ADC_STARTUP_(x) ((x) << 16) >>> #define AT91_ADC_SHTIM (0xf << 24) /* Sample & >>> Hold Time */ >>> #define AT91_ADC_SHTIM_(x) ((x) << 24) >>> @@ -58,4 +61,6 @@ >>> #define AT91_ADC_CHR(n) (0x30 + ((n) * 4)) /* Channel >>> Data Register N */ >>> #define AT91_ADC_DATA (0x3ff) >>> +#define AT91_ADC_VERSION 0xFC >>> + >>> #endif >>> diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c >>> index 18bd54f..14e99ba 100644 >>> --- a/drivers/iio/adc/at91_adc.c >>> +++ b/drivers/iio/adc/at91_adc.c >>> @@ -39,6 +39,12 @@ >>> #define at91_adc_writel(st, reg, val) \ >>> (writel_relaxed(val, st->reg_base + reg)) >>> +struct at91_adc_caps { >>> + bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */ >>> + u32 mr_prescal_mask; >>> + u32 mr_startup_mask; >>> +}; >>> + >>> struct at91_adc_state { >>> struct clk *adc_clk; >>> u16 *buffer; >>> @@ -62,6 +68,7 @@ struct at91_adc_state { >>> u32 res; /* resolution used for convertions */ >>> bool low_res; /* the resolution corresponds to >>> the lowest one */ >>> wait_queue_head_t wq_data_avail; >>> + struct at91_adc_caps caps; >>> }; >>> static irqreturn_t at91_adc_trigger_handler(int irq, void *p) >>> @@ -580,6 +587,41 @@ static const struct iio_info at91_adc_info = { >>> .read_raw = &at91_adc_read_raw, >>> }; >>> +/* >>> + * Since atmel adc support different ip for touchscreen mode. >>> Through the >>> + * IP check, we will know the touchscreen capbilities. >>> + */ >>> +static void atmel_adc_get_cap(struct at91_adc_state *st) >>> +{ >>> + unsigned int version; >>> + struct iio_dev *idev = iio_priv_to_dev(st); >>> + >>> + version = at91_adc_readl(st, AT91_ADC_VERSION); >>> + dev_dbg(&idev->dev, "version: 0x%x\n", version); >>> + >>> + st->caps.mr_prescal_mask = AT91_ADC_PRESCAL_9260; >>> + st->caps.mr_startup_mask = AT91_ADC_STARTUP_9260; >>> + >>> + /* keep only major version number */ >>> + switch (version & 0xf00) { >>> + case 0x500: /* SAMA5D3 */ >>> + case 0x400: /* AT91SAM9X5/9N12 */ >>> + st->caps.has_tsmr = 1; >>> + st->caps.mr_startup_mask = AT91_ADC_STARTUP; >>> + case 0x200: /* AT91SAM9M10/9G45 */ >>> + st->caps.mr_prescal_mask = AT91_ADC_PRESCAL; >>> + >>> + if ((version & 0xf00) == 0x200) >>> + st->caps.mr_startup_mask = AT91_ADC_STARTUP_9G45; >>> + case 0x100: /* AT91SAM9260/9G20 */ >>> + break; >>> + default: >>> + dev_warn(&idev->dev, >>> + "Unmanaged adc version, use minimal capabilities\n"); >>> + break; >>> + }; >>> +} >> Why don't you use different compatible names and derive your >> capabilities from which compatible is declared. >> >> It seems safer. I see it as handier in the sense that a different IP version can be compatible with an older IP version: so we do not need to modify the driver just to use another SoC. On your side Maxime, what makes you say that it is "safer"? > Ok, that make sense. I will use compatible names for the capabilities in > next version. Thanks. Hold on a little bit Josh, I know that Jean-Christophe is not in favor of the use of multiple compatible strings. So, as the code is already there, let's wait and see if we find another argument... Bye, -- Nicolas Ferre