ARM: 6033/1: ARM: MMCI: pass max frequency from platform

This introduce the field f_max into the mmci_platform_data,
making it possible to pass in a desired block clocking frequency
from a board configuration. This is often more desirable than
using a module parameter. We keep the module parameter as a
fallback as well as the default frequency specified for this
parameter if a parameter is not provided.

This also adds some kerneldoc style documentation to the
platform data struct in mmci.h.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Linus Walleij 2010-04-08 07:39:38 +01:00 committed by Russell King
parent 771dc157e0
commit 808d97ccbe
2 changed files with 34 additions and 2 deletions

View file

@ -631,7 +631,18 @@ static int __devinit mmci_probe(struct amba_device *dev, struct amba_id *id)
mmc->ops = &mmci_ops;
mmc->f_min = (host->mclk + 511) / 512;
mmc->f_max = min(host->mclk, fmax);
/*
* If the platform data supplies a maximum operating
* frequency, this takes precedence. Else, we fall back
* to using the module parameter, which has a (low)
* default value in case it is not specified. Either
* value must not exceed the clock rate into the block,
* of course.
*/
if (plat->f_max)
mmc->f_max = min(host->mclk, plat->f_max);
else
mmc->f_max = min(host->mclk, fmax);
dev_dbg(mmc_dev(mmc), "clocking block at %u Hz\n", mmc->f_max);
#ifdef CONFIG_REGULATOR

View file

@ -6,8 +6,29 @@
#include <linux/mmc/host.h>
/**
* struct mmci_platform_data - platform configuration for the MMCI
* (also known as PL180) block.
* @f_max: the maximum operational frequency for this host in this
* platform configuration. When this is specified it takes precedence
* over the module parameter for the same frequency.
* @ocr_mask: available voltages on the 4 pins from the block, this
* is ignored if a regulator is used, see the MMC_VDD_* masks in
* mmc/host.h
* @translate_vdd: a callback function to translate a MMC_VDD_*
* mask into a value to be binary or:ed and written into the
* MMCIPWR register of the block
* @status: if no GPIO read function was given to the block in
* gpio_wp (below) this function will be called to determine
* whether a card is present in the MMC slot or not
* @gpio_wp: read this GPIO pin to see if the card is write protected
* @gpio_cd: read this GPIO pin to detect card insertion
* @capabilities: the capabilities of the block as implemented in
* this platform, signify anything MMC_CAP_* from mmc/host.h
*/
struct mmci_platform_data {
unsigned int ocr_mask; /* available voltages */
unsigned int f_max;
unsigned int ocr_mask;
u32 (*translate_vdd)(struct device *, unsigned int);
unsigned int (*status)(struct device *);
int gpio_wp;