diff mbox

sdhci: allow for eMMC 74 clock generation by controller

Message ID 55175F2E-72DD-4BB2-8EDD-70D8B553F7B6@marvell.com (mailing list archive)
State Accepted, archived
Headers show

Commit Message

Philip Rakity Sept. 23, 2010, 3:24 p.m. UTC
None
diff mbox

Patch

=============

From 1ba80b60d0ca3ba3114e2aa25f1afdb8a6af3842 Mon Sep 17 00:00:00 2001
From: Philip Rakity <prakity@marvell.com>
Date: Thu, 23 Sep 2010 08:15:03 -0700
Subject: [PATCH] sdhci: allow for initial eMMC 74 clock generation by controller

resend of patch to fit into 80 char line lengths:

snippet of code for how adaption layer should handle the call.


/*
 * eMMC spec calls for the host to send 74 clocks to the card
 * during initialization, right after voltage stabilization.
 * create the clocks manually right here.
 */
void generate_init_clocks_A0(struct sdhci_host *host, u8 power_mode)
{
	struct sdhci_mmc_slot *slot = sdhci_priv(host);

	DBG ("%s: ENTER %s: slot->power_mode = %d, ios->power_mode = %d\n",
	 	__func__, 
		mmc_hostname(host->mmc),
		slot->power_mode, 
		power_mode);

	if (slot->power_mode == MMC_POWER_UP 
	&& power_mode == MMC_POWER_ON) {
	
		/* controller specific code here */
		/* slot->power_mode holds previous power setting */
	}
	slot->power_mode = power_mode;
}


Signed-off-by: Philip Rakity <prakity@marvell.com>
---
 drivers/mmc/host/sdhci.c |    3 +++
 drivers/mmc/host/sdhci.h |    2 ++
 2 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 6b8ca32..ba8f9a0 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1169,6 +1169,9 @@  static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	else
 		sdhci_set_power(host, ios->vdd);
 
+	if (host->ops->platform_send_init_74_clocks)
+		host->ops->platform_send_init_74_clocks(host, ios->power_mode);
+
 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 
 	if (ios->bus_width == MMC_BUS_WIDTH_8)
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 290b5a8..d73685a 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -325,6 +325,8 @@  struct sdhci_ops {
 	unsigned int	(*get_max_clock)(struct sdhci_host *host);
 	unsigned int	(*get_min_clock)(struct sdhci_host *host);
 	unsigned int	(*get_timeout_clock)(struct sdhci_host *host);
+	void (*platform_send_init_74_clocks)(struct sdhci_host *host,
+		u8 power_mode);
 };
 
 #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS