[U-Boot] [PATCH v4] mmc: atmel: Add atmel sdhci support

[Wenyou Yang]

The SDHCI is introduced by sama5d2, named as Secure Digital Multimedia
Card Controller(SDMMC). It supports the embedded MultiMedia Card (e.MMC)
Specification V4.41, the SD Memory Card Specification V3.0, and the SDIO
V3.0 specification. It is compliant with the SD Host Controller Standard
V3.0 specification.

Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
---

Changes in v4:
 1./ remove unneeded initial value NULL of host.
 2./ use calloc() to zero-initialize the buffer, instead of malloc().
 3./ remove unnecessary convert type before host->ioaddr.

Changes in v3:
 1./ return -ENODEV instead of -1, when failing to get proper clock.
 2./ add free host instance when failing to get proper clock.

Changes in v2:
 - According to Bo Shen's comments,
 1./ change the macro ATMEL_SDHC_MIN_FRQ -> ATMEL_SDHC_MIN_FREQ.
 2./ change the return value to -ENOMEM and print log for malloc failure.
 3./ add the failed return and log for getting improper clock.
 4./ add more commit log.

 arch/arm/mach-at91/include/mach/atmel_sdhci.h |   13 ++++++++
 drivers/mmc/Makefile                          |    1 +
 drivers/mmc/atmel_sdhci.c                     |   40 +++++++++++++++++++++++++
 3 files changed, 54 insertions(+)
 create mode 100644 arch/arm/mach-at91/include/mach/atmel_sdhci.h
 create mode 100644 drivers/mmc/atmel_sdhci.c

diff --git a/arch/arm/mach-at91/include/mach/atmel_sdhci.h b/arch/arm/mach-at91/include/mach/atmel_sdhci.h
new file mode 100644
index 0000000..9652bc2
--- /dev/null
+++ b/arch/arm/mach-at91/include/mach/atmel_sdhci.h
@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) 2015 Atmel Corporation
+ *		      Wenyou.Yang <wenyou.yang at atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __ATMEL_SDHCI_H
+#define __ATMEL_SDHCI_H
+
+int atmel_sdhci_init(void *regbase, u32 id);
+
+#endif
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 99d0295..5d35705 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -8,6 +8,7 @@
 obj-$(CONFIG_DM_MMC) += mmc-uclass.o
 
 obj-$(CONFIG_ARM_PL180_MMCI) += arm_pl180_mmci.o
+obj-$(CONFIG_ATMEL_SDHCI) += atmel_sdhci.o
 obj-$(CONFIG_BCM2835_SDHCI) += bcm2835_sdhci.o
 obj-$(CONFIG_BFIN_SDH) += bfin_sdh.o
 obj-$(CONFIG_DAVINCI_MMC) += davinci_mmc.o
diff --git a/drivers/mmc/atmel_sdhci.c b/drivers/mmc/atmel_sdhci.c
new file mode 100644
index 0000000..1437a21
--- /dev/null
+++ b/drivers/mmc/atmel_sdhci.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2015 Atmel Corporation
+ *		      Wenyou.Yang <wenyou.yang at atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <sdhci.h>
+#include <asm/arch/clk.h>
+
+#define ATMEL_SDHC_MIN_FREQ	400000
+
+int atmel_sdhci_init(void *regbase, u32 id)
+{
+	struct sdhci_host *host;
+	u32 max_clk, min_clk = ATMEL_SDHC_MIN_FREQ;
+
+	host = (struct sdhci_host *)calloc(sizeof(struct sdhci_host));
+	if (!host) {
+		printf("%s: sdhci_host malloc failed\n", __func__);
+		return -ENOMEM;
+	}
+
+	host->name = "atmel_sdhci";
+	host->ioaddr = regbase;
+	host->quirks = 0;
+	host->version = sdhci_readw(host, SDHCI_HOST_VERSION);
+	max_clk = at91_get_periph_generated_clk(id);
+	if (!max_clk) {
+		printf("%s: Failed to get the proper clock\n", __func__);
+		free(host);
+		return -ENODEV;
+	}
+
+	add_sdhci(host, max_clk, min_clk);
+
+	return 0;
+}
-- 
1.7.9.5