mmc: tmio: split core functionality, DMA and MFD glue

TMIO MMC chips contain an SD / SDIO IP core from Panasonic, similar to
the one, used in MN5774 and other MN57xx controllers. These IP cores are
included in many multifunction devices, in sh-mobile chips from Renesas,
in the latter case they can also use DMA. Some sh-mobile implementations
also have some other specialities, that MFD-based solutions don't have.
This makes supporting all these features in a monolithic driver inconveniet
and error-prone. This patch splits the driver into 3 parts: the core,
the MFD glue and the DMA support. In case of a modular build, two modules
will be built: mmc_tmio_core and mmc_tmio.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 145 insertions, 0 deletions

diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
new file mode 100644
index 000000000000..8dedf0a69348
--- /dev/null
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -0,0 +1,145 @@
+/*
+ * linux/drivers/mmc/host/tmio_mmc.h
+ *
+ * Copyright (C) 2007 Ian Molton
+ * Copyright (C) 2004 Ian Molton
+ *
+ * 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.
+ *
+ * Driver for the MMC / SD / SDIO cell found in:
+ *
+ * TC6393XB TC6391XB TC6387XB T7L66XB ASIC3
+ */
+
+#ifndef TMIO_MMC_H
+#define TMIO_MMC_H
+
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+
+/* Definitions for values the CTRL_STATUS register can take. */
+#define TMIO_STAT_CMDRESPEND    0x00000001
+#define TMIO_STAT_DATAEND       0x00000004
+#define TMIO_STAT_CARD_REMOVE   0x00000008
+#define TMIO_STAT_CARD_INSERT   0x00000010
+#define TMIO_STAT_SIGSTATE      0x00000020
+#define TMIO_STAT_WRPROTECT     0x00000080
+#define TMIO_STAT_CARD_REMOVE_A 0x00000100
+#define TMIO_STAT_CARD_INSERT_A 0x00000200
+#define TMIO_STAT_SIGSTATE_A    0x00000400
+#define TMIO_STAT_CMD_IDX_ERR   0x00010000
+#define TMIO_STAT_CRCFAIL       0x00020000
+#define TMIO_STAT_STOPBIT_ERR   0x00040000
+#define TMIO_STAT_DATATIMEOUT   0x00080000
+#define TMIO_STAT_RXOVERFLOW    0x00100000
+#define TMIO_STAT_TXUNDERRUN    0x00200000
+#define TMIO_STAT_CMDTIMEOUT    0x00400000
+#define TMIO_STAT_RXRDY         0x01000000
+#define TMIO_STAT_TXRQ          0x02000000
+#define TMIO_STAT_ILL_FUNC      0x20000000
+#define TMIO_STAT_CMD_BUSY      0x40000000
+#define TMIO_STAT_ILL_ACCESS    0x80000000
+
+/* Definitions for values the CTRL_SDIO_STATUS register can take. */
+#define TMIO_SDIO_STAT_IOIRQ		0x0001
+#define TMIO_SDIO_STAT_EXPUB52	0x4000
+#define TMIO_SDIO_STAT_EXWT		0x8000
+#define TMIO_SDIO_MASK_ALL		0xc007
+
+/* Define some IRQ masks */
+/* This is the mask used at reset by the chip */
+#define TMIO_MASK_ALL           0x837f031d
+#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND)
+#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND)
+#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
+
+struct tmio_mmc_data;
+
+struct tmio_mmc_host {
+	void __iomem *ctl;
+	unsigned long bus_shift;
+	struct mmc_command      *cmd;
+	struct mmc_request      *mrq;
+	struct mmc_data         *data;
+	struct mmc_host         *mmc;
+	int                     irq;
+	unsigned int		sdio_irq_enabled;
+
+	/* Callbacks for clock / power control */
+	void (*set_pwr)(struct platform_device *host, int state);
+	void (*set_clk_div)(struct platform_device *host, int state);
+
+	/* pio related stuff */
+	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
+	unsigned int            sg_len;
+	unsigned int            sg_off;
+
+	struct platform_device *pdev;
+	struct tmio_mmc_data *pdata;
+
+	/* DMA support */
+	bool			force_pio;
+	struct dma_chan		*chan_rx;
+	struct dma_chan		*chan_tx;
+	struct tasklet_struct	dma_complete;
+	struct tasklet_struct	dma_issue;
+	struct scatterlist	bounce_sg;
+	u8			*bounce_buf;
+
+	/* Track lost interrupts */
+	struct delayed_work	delayed_reset_work;
+	spinlock_t		lock;
+	unsigned long		last_req_ts;
+};
+
+int tmio_mmc_host_probe(struct tmio_mmc_host **host,
+			struct platform_device *pdev,
+			struct tmio_mmc_data *pdata);
+void tmio_mmc_host_remove(struct tmio_mmc_host *host);
+void tmio_mmc_do_data_irq(struct tmio_mmc_host *host);
+
+void tmio_mmc_enable_mmc_irqs(struct tmio_mmc_host *host, u32 i);
+void tmio_mmc_disable_mmc_irqs(struct tmio_mmc_host *host, u32 i);
+
+static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
+					 unsigned long *flags)
+{
+	local_irq_save(*flags);
+	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
+}
+
+static inline void tmio_mmc_kunmap_atomic(struct scatterlist *sg,
+					  unsigned long *flags, void *virt)
+{
+	kunmap_atomic(virt - sg->offset, KM_BIO_SRC_IRQ);
+	local_irq_restore(*flags);
+}
+
+#ifdef CONFIG_TMIO_MMC_DMA
+void tmio_mmc_start_dma(struct tmio_mmc_host *host, struct mmc_data *data);
+void tmio_mmc_request_dma(struct tmio_mmc_host *host, struct tmio_mmc_data *pdata);
+void tmio_mmc_release_dma(struct tmio_mmc_host *host);
+#else
+static inline void tmio_mmc_start_dma(struct tmio_mmc_host *host,
+			       struct mmc_data *data)
+{
+}
+
+static inline void tmio_mmc_request_dma(struct tmio_mmc_host *host,
+				 struct tmio_mmc_data *pdata)
+{
+	host->chan_tx = NULL;
+	host->chan_rx = NULL;
+}
+
+static inline void tmio_mmc_release_dma(struct tmio_mmc_host *host)
+{
+}
+#endif
+
+#endif