mmc: Driver for CB710/720 memory card reader (MMC part)

The code is divided in two parts. There is a virtual 'bus' driver
that handles PCI device and registers three new devices one per card
reader type. The other driver handles SD/MMC part of the reader.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>

1 files changed, 238 insertions, 0 deletions

diff --git a/include/linux/cb710.h b/include/linux/cb710.h
new file mode 100644
index 000000000000..c3819e1ce1c6
--- /dev/null
+++ b/include/linux/cb710.h
@@ -0,0 +1,238 @@
+/*
+ *  cb710/cb710.h
+ *
+ *  Copyright by Michał Mirosław, 2008-2009
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef LINUX_CB710_DRIVER_H
+#define LINUX_CB710_DRIVER_H
+
+#ifdef CONFIG_CB710_DEBUG
+#define DEBUG
+#endif
+
+/* verify assumptions on platform_device framework */
+#define CONFIG_CB710_DEBUG_ASSUMPTIONS
+
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/mmc/host.h>
+
+struct cb710_slot;
+
+typedef int (*cb710_irq_handler_t)(struct cb710_slot *);
+
+/* per-virtual-slot structure */
+struct cb710_slot {
+	struct platform_device	pdev;
+	void __iomem		*iobase;
+	cb710_irq_handler_t	irq_handler;
+};
+
+/* per-device structure */
+struct cb710_chip {
+	struct pci_dev		*pdev;
+	void __iomem		*iobase;
+	unsigned		platform_id;
+#ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
+	atomic_t		slot_refs_count;
+#endif
+	unsigned		slot_mask;
+	unsigned		slots;
+	spinlock_t		irq_lock;
+	struct cb710_slot	slot[0];
+};
+
+/* NOTE: cb710_chip.slots is modified only during device init/exit and
+ * they are all serialized wrt themselves */
+
+/* cb710_chip.slot_mask values */
+#define CB710_SLOT_MMC		1
+#define CB710_SLOT_MS		2
+#define CB710_SLOT_SM		4
+
+/* slot port accessors - so the logic is more clear in the code */
+#define CB710_PORT_ACCESSORS(t) \
+static inline void cb710_write_port_##t(struct cb710_slot *slot,	\
+	unsigned port, u##t value)					\
+{									\
+	iowrite##t(value, slot->iobase + port);				\
+}									\
+									\
+static inline u##t cb710_read_port_##t(struct cb710_slot *slot,		\
+	unsigned port)							\
+{									\
+	return ioread##t(slot->iobase + port);				\
+}									\
+									\
+static inline void cb710_modify_port_##t(struct cb710_slot *slot,	\
+	unsigned port, u##t set, u##t clear)				\
+{									\
+	iowrite##t(							\
+		(ioread##t(slot->iobase + port) & ~clear)|set,		\
+		slot->iobase + port);					\
+}
+
+CB710_PORT_ACCESSORS(8)
+CB710_PORT_ACCESSORS(16)
+CB710_PORT_ACCESSORS(32)
+
+void cb710_pci_update_config_reg(struct pci_dev *pdev,
+	int reg, uint32_t and, uint32_t xor);
+void cb710_set_irq_handler(struct cb710_slot *slot,
+	cb710_irq_handler_t handler);
+
+/* some device struct walking */
+
+static inline struct cb710_slot *cb710_pdev_to_slot(
+	struct platform_device *pdev)
+{
+	return container_of(pdev, struct cb710_slot, pdev);
+}
+
+static inline struct cb710_chip *cb710_slot_to_chip(struct cb710_slot *slot)
+{
+	return dev_get_drvdata(slot->pdev.dev.parent);
+}
+
+static inline struct device *cb710_slot_dev(struct cb710_slot *slot)
+{
+	return &slot->pdev.dev;
+}
+
+static inline struct device *cb710_chip_dev(struct cb710_chip *chip)
+{
+	return &chip->pdev->dev;
+}
+
+/* debugging aids */
+
+#ifdef CONFIG_CB710_DEBUG
+void cb710_dump_regs(struct cb710_chip *chip, unsigned dump);
+#else
+#define cb710_dump_regs(c, d) do {} while (0)
+#endif
+
+#define CB710_DUMP_REGS_MMC	0x0F
+#define CB710_DUMP_REGS_MS	0x30
+#define CB710_DUMP_REGS_SM	0xC0
+#define CB710_DUMP_REGS_ALL	0xFF
+#define CB710_DUMP_REGS_MASK	0xFF
+
+#define CB710_DUMP_ACCESS_8	0x100
+#define CB710_DUMP_ACCESS_16	0x200
+#define CB710_DUMP_ACCESS_32	0x400
+#define CB710_DUMP_ACCESS_ALL	0x700
+#define CB710_DUMP_ACCESS_MASK	0x700
+
+#endif /* LINUX_CB710_DRIVER_H */
+/*
+ *  cb710/sgbuf2.h
+ *
+ *  Copyright by Michał Mirosław, 2008-2009
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef LINUX_CB710_SG_H
+#define LINUX_CB710_SG_H
+
+#include <linux/highmem.h>
+#include <linux/scatterlist.h>
+
+/**
+ * cb710_sg_miter_stop_writing - stop mapping iteration after writing
+ * @miter: sg mapping iter to be stopped
+ *
+ * Description:
+ *   Stops mapping iterator @miter.  @miter should have been started
+ *   started using sg_miter_start().  A stopped iteration can be
+ *   resumed by calling sg_miter_next() on it.  This is useful when
+ *   resources (kmap) need to be released during iteration.
+ *
+ *   This is a convenience wrapper that will be optimized out for arches
+ *   that don't need flush_kernel_dcache_page().
+ *
+ * Context:
+ *   IRQ disabled if the SG_MITER_ATOMIC is set.  Don't care otherwise.
+ */
+static inline void cb710_sg_miter_stop_writing(struct sg_mapping_iter *miter)
+{
+	if (miter->page)
+		flush_kernel_dcache_page(miter->page);
+	sg_miter_stop(miter);
+}
+
+/*
+ * 32-bit PIO mapping sg iterator
+ *
+ * Hides scatterlist access issues - fragment boundaries, alignment, page
+ * mapping - for drivers using 32-bit-word-at-a-time-PIO (ie. PCI devices
+ * without DMA support).
+ *
+ * Best-case reading (transfer from device):
+ *   sg_miter_start();
+ *   cb710_sg_dwiter_write_from_io();
+ *   cb710_sg_miter_stop_writing();
+ *
+ * Best-case writing (transfer to device):
+ *   sg_miter_start();
+ *   cb710_sg_dwiter_read_to_io();
+ *   sg_miter_stop();
+ */
+
+uint32_t cb710_sg_dwiter_read_next_block(struct sg_mapping_iter *miter);
+void cb710_sg_dwiter_write_next_block(struct sg_mapping_iter *miter, uint32_t data);
+
+/**
+ * cb710_sg_dwiter_write_from_io - transfer data to mapped buffer from 32-bit IO port
+ * @miter: sg mapping iter
+ * @port: PIO port - IO or MMIO address
+ * @count: number of 32-bit words to transfer
+ *
+ * Description:
+ *   Reads @count 32-bit words from register @port and stores it in
+ *   buffer iterated by @miter.  Data that would overflow the buffer
+ *   is silently ignored.  Iterator is advanced by 4*@count bytes
+ *   or to the buffer's end whichever is closer.
+ *
+ * Context:
+ *   IRQ disabled if the SG_MITER_ATOMIC is set.  Don't care otherwise.
+ */
+static inline void cb710_sg_dwiter_write_from_io(struct sg_mapping_iter *miter,
+	void __iomem *port, size_t count)
+{
+	while (count-- > 0)
+		cb710_sg_dwiter_write_next_block(miter, ioread32(port));
+}
+
+/**
+ * cb710_sg_dwiter_read_to_io - transfer data to 32-bit IO port from mapped buffer
+ * @miter: sg mapping iter
+ * @port: PIO port - IO or MMIO address
+ * @count: number of 32-bit words to transfer
+ *
+ * Description:
+ *   Writes @count 32-bit words to register @port from buffer iterated
+ *   through @miter.  If buffer ends before @count words are written
+ *   missing data is replaced by zeroes. @miter is advanced by 4*@count
+ *   bytes or to the buffer's end whichever is closer.
+ *
+ * Context:
+ *   IRQ disabled if the SG_MITER_ATOMIC is set.  Don't care otherwise.
+ */
+static inline void cb710_sg_dwiter_read_to_io(struct sg_mapping_iter *miter,
+	void __iomem *port, size_t count)
+{
+	while (count-- > 0)
+		iowrite32(cb710_sg_dwiter_read_next_block(miter), port);
+}
+
+#endif /* LINUX_CB710_SG_H */