2011-10-23 23:05:26     User space SPIDEV Why use the ". Chip_select = 1,"?

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2011-10-23 23:05:26     User space SPIDEV Why use the ". Chip_select = 1,"?

qian xin (CHINA)

Message: 104117   

 

hi

     all.

 

    When I use SPIDEV to realize a SPI character device,needs to select in the Kernel configuration:

<*>   User mode SPI device driver support  。(SPI_SPIDEV [=y])

 

My question:

 

/bf561/board/ezkit.c

 

#if defined(CONFIG_SPI_SPIDEV) || defined(CONFIG_SPI_SPIDEV_MODULE)

     {

         .modalias = "spidev",

         .max_speed_hz = 3125000,     /* max spi clock (SCK) speed in HZ */

         .bus_num = 0,

         .chip_select = 1,

         .controller_data = &spidev_chip_info,

     },

#endif

 

 

I did not understand that .chip_select = 1, which one was uses from the device.

 

“.chip_select = 1,” and PF1 multiplying in the bf561。The PF1 pin in I design, is taken.

 

When why I do select “User mode SPI device driver support”, must found spidev0.1 the equipment?

 

The PF1 pin in mine design, has been taken by GPIO_keys, what solution has?

 

Thank you.

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2011-10-23 23:13:22     Re: User space SPIDEV Why use the ". Chip_select = 1,"?

Aaron Wu (CHINA)

Message: 104119   

 

We will have a look. Appreciate very much if you could move your question to our engineerzone as this forum will be replaced by it, details here:

 

  blackfin.uclinux.org/gf/project/u-boot/forum/?_forum_action=MessageReply&action=ForumBrowse&message_id=103911

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