No subject

-----------------------------------------------------------------------------
        /* Look for the fastest read cmd */
        cmd = fls(params->rd_cmd & flash->spi->rd_cmd);
        if (cmd) {
                cmd = spi_read_cmds_array[cmd - 1];
                flash->read_cmd = cmd;
        } else {
                /* Go for controller supported command */
                flash->read_cmd = CMD_READ_ARRAY_FAST;
        }

        /* Look for the fastest write cmd */
        cmd = fls(params->wr_cmd & flash->spi->wr_cmd);
        if (cmd) {
                cmd = spi_write_cmds_array[cmd - 1];
                flash->write_cmd = cmd;
        } else {
                /* Go for controller supported command */
                flash->write_cmd = CMD_PAGE_PROGRAM;
        }

include/spi_flash.h:
---------------------------
/* Supported write cmds enum list */
enum spi_write_cmds {
        PAGE_PROGRAM = 1 << 0,
        QUAD_PAGE_PROGRAM = 1 << 1,
};
#define WR_CMD_FULL             PAGE_PROGRAM | QUAD_PAGE_PROGRAM

/* Supported read cmds enum list */
enum spi_read_cmds {
        ARRAY_SLOW = 1 << 0,
        ARRAY_FAST = 1 << 1,
        DUAL_OUTPUT_FAST = 1 << 2,
        DUAL_IO_FAST = 1 << 3,
        QUAD_OUTPUT_FAST = 1 << 4,
};
#define RD_CMD_FULL     ARRAY_SLOW | ARRAY_FAST | DUAL_OUTPUT_FAST | \
                        DUAL_IO_FAST | QUAD_OUTPUT_FAST


If the controller is not filling slave.rd_cmd and slave.wr_cmd if it's
not supporting even if connected flash
supports, fill the read/write commands to default ones.

Controller is a master to decide which command is to use, and flash is
slave to transfer the discovered command
through spi_xfer(), so the controller will take care of the command processing.

This is well detailed explanation, I hope you understand.

>
> Maybe your specific controller behaves in another way, but this is not the standard
> and you should not force this into the interface.
>
> And another doubt: The might be different commands for dual/quad read/write,
> depending on the flash manufacturer. With your solution, the controller drivers
> would need these details in advance! Or at least need to be updated on each new
> command, which needs to be supported.
>
>> --
>> Thanks,
>> Jagan.
>
> Best Regards,
> Thomas
>
>

-- 
Thanks,
Jagan.
--------
Jagannadha Sutradharudu Teki,
E: jagannadh.teki at gmail.com, P: +91-9676773388
Engineer - System Software Hacker
U-boot - SPI Custodian and Zynq APSOC
Ln: http://www.linkedin.com/in/jaganteki