[PATCH linux dev-4.17 5/7] mmc: Aspeed: Add driver for Aspeed sdhci

Ryan Chen ryanchen.aspeed at gmail.com
Wed Jul 11 15:17:08 AEST 2018


Add a driver for Aspeed's sdhci controller core.

Signed-off-by: Ryan Chen <ryanchen.aspeed at gmail.com>
---
 drivers/mmc/host/Kconfig           |  12 +++
 drivers/mmc/host/Makefile          |   1 +
 drivers/mmc/host/sdhci-of-aspeed.c | 178 +++++++++++++++++++++++++++++++++++++
 3 files changed, 191 insertions(+)
 create mode 100644 drivers/mmc/host/sdhci-of-aspeed.c

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 9589f9c..5056e6e 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -142,6 +142,18 @@ config MMC_SDHCI_OF_ARASAN
 
 	  If unsure, say N.
 
+config MMC_SDHCI_OF_ASPEED
+	tristate "SDHCI OF support for the ASPEED SDHCI controller"
+	depends on MMC_SDHCI_PLTFM
+	depends on OF
+	help
+	  This selects the ASPEED Secure Digital Host Controller Interface.
+
+	  If you have a controller with this interface, say Y or M here. You
+	  also need to enable an appropriate bus interface.
+
+	  If unsure, say N.
+
 config MMC_SDHCI_OF_AT91
 	tristate "SDHCI OF support for the Atmel SDMMC controller"
 	depends on MMC_SDHCI_PLTFM
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 6aead24..084193b 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -78,6 +78,7 @@ obj-$(CONFIG_MMC_SDHCI_ESDHC_IMX)	+= sdhci-esdhc-imx.o
 obj-$(CONFIG_MMC_SDHCI_DOVE)		+= sdhci-dove.o
 obj-$(CONFIG_MMC_SDHCI_TEGRA)		+= sdhci-tegra.o
 obj-$(CONFIG_MMC_SDHCI_OF_ARASAN)	+= sdhci-of-arasan.o
+obj-$(CONFIG_MMC_SDHCI_OF_ASPEED)	+= sdhci-of-aspeed.o
 obj-$(CONFIG_MMC_SDHCI_OF_AT91)		+= sdhci-of-at91.o
 obj-$(CONFIG_MMC_SDHCI_OF_ESDHC)	+= sdhci-of-esdhc.o
 obj-$(CONFIG_MMC_SDHCI_OF_HLWD)		+= sdhci-of-hlwd.o
diff --git a/drivers/mmc/host/sdhci-of-aspeed.c b/drivers/mmc/host/sdhci-of-aspeed.c
new file mode 100644
index 0000000..8e609e1
--- /dev/null
+++ b/drivers/mmc/host/sdhci-of-aspeed.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ASPEED Secure Digital Host Controller Interface.
+ * Copyright (C) ASPEED Technology Inc.
+ * Ryan Chen <ryan_chen at aspeedtech.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/mmc/host.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/mmc/sdhci-aspeed-data.h>
+#include <linux/reset.h>
+#include "sdhci-pltfm.h"
+
+static void sdhci_aspeed_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	int div;
+	u16 clk;
+	unsigned long timeout;
+
+	if (clock == host->clock)
+		return;
+
+	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+
+	if (clock == 0)
+		goto out;
+
+	for (div = 1; div < 256; div *= 2) {
+		if ((host->max_clk / div) <= clock)
+			break;
+	}
+	div >>= 1;
+
+	clk = div << SDHCI_DIVIDER_SHIFT;
+	clk |= SDHCI_CLOCK_INT_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+	/* Wait max 20 ms */
+	timeout = 20;
+	while (!((clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
+		 & SDHCI_CLOCK_INT_STABLE)) {
+		if (timeout == 0) {
+			pr_err("%s: Internal clock never stabilised.\n",
+			       mmc_hostname(host->mmc));
+			return;
+		}
+		timeout--;
+		mdelay(1);
+	}
+
+	clk |= SDHCI_CLOCK_CARD_EN;
+	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+out:
+	host->clock = clock;
+}
+
+static void sdhci_aspeed_set_bus_width(struct sdhci_host *host, int width)
+{
+	struct sdhci_pltfm_host *pltfm_priv = sdhci_priv(host);
+	struct aspeed_sdhci_irq *sdhci_irq = sdhci_pltfm_priv(pltfm_priv);
+
+	u8 ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
+
+	if (sdhci_irq->regs) {
+		if (width == MMC_BUS_WIDTH_8)
+			aspeed_sdhci_set_8bit_mode(sdhci_irq, 1);
+		else
+			aspeed_sdhci_set_8bit_mode(sdhci_irq, 0);
+	}
+	if (width == MMC_BUS_WIDTH_4)
+		ctrl |= SDHCI_CTRL_4BITBUS;
+	else
+		ctrl &= ~SDHCI_CTRL_4BITBUS;
+
+	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+
+}
+
+static struct sdhci_ops  sdhci_aspeed_ops = {
+	.set_clock = sdhci_aspeed_set_clock,
+	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
+	.set_bus_width = sdhci_aspeed_set_bus_width,
+	.get_timeout_clock = sdhci_pltfm_clk_get_max_clock,
+	.reset = sdhci_reset,
+	.set_uhs_signaling = sdhci_set_uhs_signaling,
+};
+
+static struct sdhci_pltfm_data sdhci_aspeed_pdata = {
+	.ops = &sdhci_aspeed_ops,
+	.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
+	.quirks2 = SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
+};
+
+static int sdhci_aspeed_probe(struct platform_device *pdev)
+{
+	struct sdhci_host *host;
+	struct device_node *pnode;
+	struct device_node *np = pdev->dev.of_node;
+	struct sdhci_pltfm_host *pltfm_host;
+	struct aspeed_sdhci_irq *sdhci_irq;
+
+	int ret;
+
+	host = sdhci_pltfm_init(pdev, &sdhci_aspeed_pdata, sizeof(struct aspeed_sdhci_irq));
+	if (IS_ERR(host))
+		return PTR_ERR(host);
+
+	pltfm_host = sdhci_priv(host);
+	sdhci_irq = sdhci_pltfm_priv(pltfm_host);
+
+	sdhci_get_of_property(pdev);
+
+	pltfm_host->clk = devm_clk_get(&pdev->dev, NULL);
+
+	pnode = of_parse_phandle(np, "interrupt-parent", 0);
+	if (pnode)
+		memcpy(sdhci_irq, pnode->data, sizeof(struct aspeed_sdhci_irq));
+
+	ret = mmc_of_parse(host->mmc);
+	if (ret)
+		goto err_sdhci_add;
+
+	ret = sdhci_add_host(host);
+	if (ret)
+		goto err_sdhci_add;
+
+	return 0;
+
+err_sdhci_add:
+	sdhci_pltfm_free(pdev);
+	return ret;
+}
+
+static int sdhci_aspeed_remove(struct platform_device *pdev)
+{
+	struct sdhci_host	*host = platform_get_drvdata(pdev);
+	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
+
+	sdhci_remove_host(host, dead);
+	sdhci_pltfm_free(pdev);
+	return 0;
+}
+
+static const struct of_device_id sdhci_aspeed_of_match[] = {
+	{ .compatible = "aspeed,sdhci-ast2400", .data = &sdhci_aspeed_pdata },
+	{ .compatible = "aspeed,sdhci-ast2500", .data = &sdhci_aspeed_pdata },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, sdhci_aspeed_of_match);
+
+static struct platform_driver sdhci_aspeed_driver = {
+	.driver		= {
+		.name	= "sdhci-aspeed",
+		.pm	= &sdhci_pltfm_pmops,
+		.of_match_table = sdhci_aspeed_of_match,
+	},
+	.probe		= sdhci_aspeed_probe,
+	.remove		= sdhci_aspeed_remove,
+};
+
+module_platform_driver(sdhci_aspeed_driver);
+
+MODULE_DESCRIPTION("Driver for the ASPEED SDHCI Controller");
+MODULE_AUTHOR("Ryan Chen <ryan_chen at aspeedtech.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4



More information about the openbmc mailing list