[PATCH V20 09/22] mmc: sdhci: add UHS-II module and add a kernel configuration

Victor Shih
2024-09-05T10:20:44Z

This patch adds sdhci-uhs2.c as a module for UHS-II support.
This is a skeleton for further development in this patch series.

This kernel configuration, CONFIG_MMC_SDHCI_UHS2, will be used
in the following commits to indicate UHS-II specific code in sdhci
controllers.

Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Victor Shih <victor.shih@genesyslogic.com.tw>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
---

Updates in V9:
- Modify the commit message.

Updates in V8:
- Modify MODULE_LICENSE from "GPL v2" to "GPL".

Updates in V6:
- Merage V5 of patch[7] and patch[9] in to V6 of patch[8].

---

drivers/mmc/host/Kconfig | 9 +++++++
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/sdhci-uhs2.c | 46 +++++++++++++++++++++++++++++++++++
3 files changed, 56 insertions(+)
create mode 100644 drivers/mmc/host/sdhci-uhs2.c

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 7199cb0bd0b9..f636af8a98df 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -98,6 +98,15 @@ config MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER

This is the case for the Nintendo Wii SDHCI.

+config MMC_SDHCI_UHS2
+ tristate "UHS2 support on SDHCI controller"
+ depends on MMC_SDHCI
+ help
+ This option is selected by SDHCI controller drivers that want to
+ support UHS2-capable devices.
+
+ If you have a controller with this feature, say Y or M here.
+
config MMC_SDHCI_PCI
tristate "SDHCI support on PCI bus"
depends on MMC_SDHCI && PCI
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 3ccffebbe59b..5147467ec825 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_MMC_PXA) += pxamci.o
obj-$(CONFIG_MMC_MXC) += mxcmmc.o
obj-$(CONFIG_MMC_MXS) += mxs-mmc.o
obj-$(CONFIG_MMC_SDHCI) += sdhci.o
+obj-$(CONFIG_MMC_SDHCI_UHS2) += sdhci-uhs2.o
obj-$(CONFIG_MMC_SDHCI_PCI) += sdhci-pci.o
sdhci-pci-y += sdhci-pci-core.o sdhci-pci-o2micro.o sdhci-pci-arasan.o \
sdhci-pci-dwc-mshc.o sdhci-pci-gli.o
diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
new file mode 100644
index 000000000000..608f8ad5aaed
--- /dev/null
+++ b/drivers/mmc/host/sdhci-uhs2.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * linux/drivers/mmc/host/sdhci_uhs2.c - Secure Digital Host Controller
+ * Interface driver
+ *
+ * Copyright (C) 2014 Intel Corp, All Rights Reserved.
+ * Copyright (C) 2020 Genesys Logic, Inc.
+ * Authors: Ben Chuang <ben.chuang@genesyslogic.com.tw>
+ * Copyright (C) 2020 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ */
+
+#include <linux/module.h>
+
+#include "sdhci.h"
+#include "sdhci-uhs2.h"
+
+#define DRIVER_NAME "sdhci_uhs2"
+#define DBG(f, x...) \
+ pr_debug(DRIVER_NAME " [%s()]: " f, __func__, ## x)
+
+/*****************************************************************************\
+ * *
+ * Driver init/exit *
+ * *
+\*****************************************************************************/
+
+static int sdhci_uhs2_host_ops_init(struct sdhci_host *host)
+{
+ return 0;
+}
+
+static int __init sdhci_uhs2_mod_init(void)
+{
+ return 0;
+}
+module_init(sdhci_uhs2_mod_init);
+
+static void __exit sdhci_uhs2_mod_exit(void)
+{
+}
+module_exit(sdhci_uhs2_mod_exit);
+
+MODULE_AUTHOR("Intel, Genesys Logic, Linaro");
+MODULE_DESCRIPTION("MMC UHS-II Support");
+MODULE_LICENSE("GPL");
--
2.25.1