Hi, Joachim,
> -----Original Message----- > From: Joachim Eastwood [mailto:[email protected]] > Sent: 2013年2月28日 3:41 > To: Yang, Wenyou > Cc: [email protected]; [email protected]; Ferre, > Nicolas; [email protected]; [email protected]; Lin, JM; > [email protected] > Subject: Re: [PATCH Resend v5 02/16] spi/spi-atmel: detect the capabilities of > SPI core by reading the VERSION register. > > On 27 February 2013 01:38, Wenyou Yang <[email protected]> wrote: > > The "has_dma_support" needed for future use with dmaengine driver. > > > > Signed-off-by: Wenyou Yang <[email protected]> > > Cc: [email protected] > > Cc: [email protected] > > --- > > drivers/spi/spi-atmel.c | 70 > ++++++++++++++++++++++++++++++++++++++--------- > > 1 file changed, 57 insertions(+), 13 deletions(-) > > > > diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c > > index 5bf3786..a8e091b 100644 > > --- a/drivers/spi/spi-atmel.c > > +++ b/drivers/spi/spi-atmel.c > > @@ -39,6 +39,7 @@ > > #define SPI_CSR1 0x0034 > > #define SPI_CSR2 0x0038 > > #define SPI_CSR3 0x003c > > +#define SPI_VERSION 0x00fc > > #define SPI_RPR 0x0100 > > #define SPI_RCR 0x0104 > > #define SPI_TPR 0x0108 > > @@ -71,6 +72,8 @@ > > #define SPI_FDIV_SIZE 1 > > #define SPI_MODFDIS_OFFSET 4 > > #define SPI_MODFDIS_SIZE 1 > > +#define SPI_WDRBT_OFFSET 5 > > +#define SPI_WDRBT_SIZE 1 > > #define SPI_LLB_OFFSET 7 > > #define SPI_LLB_SIZE 1 > > #define SPI_PCS_OFFSET 16 > > @@ -180,6 +183,11 @@ > > #define spi_writel(port,reg,value) \ > > __raw_writel((value), (port)->regs + SPI_##reg) > > > > +struct atmel_spi_caps { > > + bool is_spi2; > > + bool has_wdrbt; > > + bool has_dma_support; > > +}; > > > > /* > > * The core SPI transfer engine just talks to a register bank to set up > > @@ -204,6 +212,8 @@ struct atmel_spi { > > > > void *buffer; > > dma_addr_t buffer_dma; > > + > > + struct atmel_spi_caps caps; > > }; > > > > /* Controller-specific per-slave state */ > > @@ -222,14 +232,10 @@ struct atmel_spi_device { > > * - SPI_SR.TXEMPTY, SPI_SR.NSSR (and corresponding irqs) > > * - SPI_CSRx.CSAAT > > * - SPI_CSRx.SBCR allows faster clocking > > - * > > - * We can determine the controller version by reading the VERSION > > - * register, but I haven't checked that it exists on all chips, and > > - * this is cheaper anyway. > > */ > > -static bool atmel_spi_is_v2(void) > > +static bool atmel_spi_is_v2(struct atmel_spi *as) > > { > > - return !cpu_is_at91rm9200(); > > + return as->caps.is_spi2; > > } > > Since you are removing cpu_is_at91rm9200() you might want to remove > the mach/cpu.h include as well. I ignored it , you are right. > > Regarding the includes. I think asm/{io.h, gpio.h} should be converted > to linux/{io.h, gpio.h}. In it's own patch, though. > I tried it, it is OK > <snip> > > > @@ -910,6 +921,32 @@ static void atmel_spi_cleanup(struct spi_device > *spi) > > kfree(asd); > > } > > > > +static inline unsigned int atmel_get_version(struct atmel_spi *as) > > +{ > > + return spi_readl(as, VERSION) & 0x00000fff; > > +} > > + > > +static void __init atmel_get_caps(struct atmel_spi *as) > > +{ > > + unsigned int version; > > + > > + version = atmel_get_version(as); > > + dev_info(&as->pdev->dev, "version: 0x%x\n", version); > > + > > + as->caps.is_spi2 = false; > > + as->caps.has_wdrbt = false; > > + as->caps.has_dma_support = false; > > + > > + if (version > 0x121) > > + as->caps.is_spi2 = true; > > + > > + if (version >= 0x210) > > + as->caps.has_wdrbt = true; > > + > > + if (version >= 0x212) > > + as->caps.has_dma_support = true; > > +} > > This could be just written as: as->caps.has_dma_support = (version >= 0x212); > or using a conditional. > > It would save some lines. > You are right. > regards > Joachim Eastwood ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_d2d_feb _______________________________________________ spi-devel-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/spi-devel-general
