sudmac: add support for SUDMAC
authorShimoda, Yoshihiro <yoshihiro.shimoda.uh@renesas.com>
Tue, 23 Apr 2013 11:00:12 +0000 (20:00 +0900)
committerVinod Koul <vinod.koul@intel.com>
Tue, 30 Apr 2013 10:20:12 +0000 (15:50 +0530)
Some Renesas USB modules have SUDMAC. This patch supports it using
the shdma-base driver.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
drivers/dma/sh/Kconfig
drivers/dma/sh/Makefile
drivers/dma/sh/sudmac.c [new file with mode: 0644]
include/linux/sudmac.h [new file with mode: 0644]

index c0f7a37..5c1dee2 100644 (file)
@@ -16,3 +16,9 @@ config SH_DMAE
        depends on SH_DMAE_BASE
        help
          Enable support for the Renesas SuperH DMA controllers.
+
+config SUDMAC
+       tristate "Renesas SUDMAC support"
+       depends on SH_DMAE_BASE
+       help
+         Enable support for the Renesas SUDMAC controllers.
index eceaf46..c07ca46 100644 (file)
@@ -1,2 +1,3 @@
 obj-$(CONFIG_SH_DMAE_BASE) += shdma-base.o
 obj-$(CONFIG_SH_DMAE) += shdma.o
+obj-$(CONFIG_SUDMAC) += sudmac.o
diff --git a/drivers/dma/sh/sudmac.c b/drivers/dma/sh/sudmac.c
new file mode 100644 (file)
index 0000000..e7c94bb
--- /dev/null
@@ -0,0 +1,428 @@
+/*
+ * Renesas SUDMAC support
+ *
+ * Copyright (C) 2013 Renesas Solutions Corp.
+ *
+ * based on drivers/dma/sh/shdma.c:
+ * Copyright (C) 2011-2012 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
+ * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
+ * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/sudmac.h>
+
+struct sudmac_chan {
+       struct shdma_chan shdma_chan;
+       void __iomem *base;
+       char dev_id[16];        /* unique name per DMAC of channel */
+
+       u32 offset;             /* for CFG, BA, BBC, CA, CBC, DEN */
+       u32 cfg;
+       u32 dint_end_bit;
+};
+
+struct sudmac_device {
+       struct shdma_dev shdma_dev;
+       struct sudmac_pdata *pdata;
+       void __iomem *chan_reg;
+};
+
+struct sudmac_regs {
+       u32 base_addr;
+       u32 base_byte_count;
+};
+
+struct sudmac_desc {
+       struct sudmac_regs hw;
+       struct shdma_desc shdma_desc;
+};
+
+#define to_chan(schan) container_of(schan, struct sudmac_chan, shdma_chan)
+#define to_desc(sdesc) container_of(sdesc, struct sudmac_desc, shdma_desc)
+#define to_sdev(sc) container_of(sc->shdma_chan.dma_chan.device, \
+                                struct sudmac_device, shdma_dev.dma_dev)
+
+/* SUDMAC register */
+#define SUDMAC_CH0CFG          0x00
+#define SUDMAC_CH0BA           0x10
+#define SUDMAC_CH0BBC          0x18
+#define SUDMAC_CH0CA           0x20
+#define SUDMAC_CH0CBC          0x28
+#define SUDMAC_CH0DEN          0x30
+#define SUDMAC_DSTSCLR         0x38
+#define SUDMAC_DBUFCTRL                0x3C
+#define SUDMAC_DINTCTRL                0x40
+#define SUDMAC_DINTSTS         0x44
+#define SUDMAC_DINTSTSCLR      0x48
+#define SUDMAC_CH0SHCTRL       0x50
+
+/* Definitions for the sudmac_channel.config */
+#define SUDMAC_SENDBUFM        0x1000 /* b12: Transmit Buffer Mode */
+#define SUDMAC_RCVENDM 0x0100 /* b8: Receive Data Transfer End Mode */
+#define SUDMAC_LBA_WAIT        0x0030 /* b5-4: Local Bus Access Wait */
+
+/* Definitions for the sudmac_channel.dint_end_bit */
+#define SUDMAC_CH1ENDE 0x0002 /* b1: Ch1 DMA Transfer End Int Enable */
+#define SUDMAC_CH0ENDE 0x0001 /* b0: Ch0 DMA Transfer End Int Enable */
+
+#define SUDMAC_DRV_NAME "sudmac"
+
+static void sudmac_writel(struct sudmac_chan *sc, u32 data, u32 reg)
+{
+       iowrite32(data, sc->base + reg);
+}
+
+static u32 sudmac_readl(struct sudmac_chan *sc, u32 reg)
+{
+       return ioread32(sc->base + reg);
+}
+
+static bool sudmac_is_busy(struct sudmac_chan *sc)
+{
+       u32 den = sudmac_readl(sc, SUDMAC_CH0DEN + sc->offset);
+
+       if (den)
+               return true; /* working */
+
+       return false; /* waiting */
+}
+
+static void sudmac_set_reg(struct sudmac_chan *sc, struct sudmac_regs *hw,
+                          struct shdma_desc *sdesc)
+{
+       sudmac_writel(sc, sc->cfg, SUDMAC_CH0CFG + sc->offset);
+       sudmac_writel(sc, hw->base_addr, SUDMAC_CH0BA + sc->offset);
+       sudmac_writel(sc, hw->base_byte_count, SUDMAC_CH0BBC + sc->offset);
+}
+
+static void sudmac_start(struct sudmac_chan *sc)
+{
+       u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL);
+
+       sudmac_writel(sc, dintctrl | sc->dint_end_bit, SUDMAC_DINTCTRL);
+       sudmac_writel(sc, 1, SUDMAC_CH0DEN + sc->offset);
+}
+
+static void sudmac_start_xfer(struct shdma_chan *schan,
+                             struct shdma_desc *sdesc)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       struct sudmac_desc *sd = to_desc(sdesc);
+
+       sudmac_set_reg(sc, &sd->hw, sdesc);
+       sudmac_start(sc);
+}
+
+static bool sudmac_channel_busy(struct shdma_chan *schan)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+
+       return sudmac_is_busy(sc);
+}
+
+static void sudmac_setup_xfer(struct shdma_chan *schan, int slave_id)
+{
+}
+
+static const struct sudmac_slave_config *sudmac_find_slave(
+       struct sudmac_chan *sc, int slave_id)
+{
+       struct sudmac_device *sdev = to_sdev(sc);
+       struct sudmac_pdata *pdata = sdev->pdata;
+       const struct sudmac_slave_config *cfg;
+       int i;
+
+       for (i = 0, cfg = pdata->slave; i < pdata->slave_num; i++, cfg++)
+               if (cfg->slave_id == slave_id)
+                       return cfg;
+
+       return NULL;
+}
+
+static int sudmac_set_slave(struct shdma_chan *schan, int slave_id, bool try)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       const struct sudmac_slave_config *cfg = sudmac_find_slave(sc, slave_id);
+
+       if (!cfg)
+               return -ENODEV;
+
+       return 0;
+}
+
+static inline void sudmac_dma_halt(struct sudmac_chan *sc)
+{
+       u32 dintctrl = sudmac_readl(sc, SUDMAC_DINTCTRL);
+
+       sudmac_writel(sc, 0, SUDMAC_CH0DEN + sc->offset);
+       sudmac_writel(sc, dintctrl & ~sc->dint_end_bit, SUDMAC_DINTCTRL);
+       sudmac_writel(sc, sc->dint_end_bit, SUDMAC_DINTSTSCLR);
+}
+
+static int sudmac_desc_setup(struct shdma_chan *schan,
+                            struct shdma_desc *sdesc,
+                            dma_addr_t src, dma_addr_t dst, size_t *len)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       struct sudmac_desc *sd = to_desc(sdesc);
+
+       dev_dbg(sc->shdma_chan.dev, "%s: src=%x, dst=%x, len=%d\n",
+               __func__, src, dst, *len);
+
+       if (*len > schan->max_xfer_len)
+               *len = schan->max_xfer_len;
+
+       if (dst)
+               sd->hw.base_addr = dst;
+       else if (src)
+               sd->hw.base_addr = src;
+       sd->hw.base_byte_count = *len;
+
+       return 0;
+}
+
+static void sudmac_halt(struct shdma_chan *schan)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+
+       sudmac_dma_halt(sc);
+}
+
+static bool sudmac_chan_irq(struct shdma_chan *schan, int irq)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       u32 dintsts = sudmac_readl(sc, SUDMAC_DINTSTS);
+
+       if (!(dintsts & sc->dint_end_bit))
+               return false;
+
+       /* DMA stop */
+       sudmac_dma_halt(sc);
+
+       return true;
+}
+
+static size_t sudmac_get_partial(struct shdma_chan *schan,
+                                struct shdma_desc *sdesc)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       struct sudmac_desc *sd = to_desc(sdesc);
+       u32 current_byte_count = sudmac_readl(sc, SUDMAC_CH0CBC + sc->offset);
+
+       return sd->hw.base_byte_count - current_byte_count;
+}
+
+static bool sudmac_desc_completed(struct shdma_chan *schan,
+                                 struct shdma_desc *sdesc)
+{
+       struct sudmac_chan *sc = to_chan(schan);
+       struct sudmac_desc *sd = to_desc(sdesc);
+       u32 current_addr = sudmac_readl(sc, SUDMAC_CH0CA + sc->offset);
+
+       return sd->hw.base_addr + sd->hw.base_byte_count == current_addr;
+}
+
+static int sudmac_chan_probe(struct sudmac_device *su_dev, int id, int irq,
+                            unsigned long flags)
+{
+       struct shdma_dev *sdev = &su_dev->shdma_dev;
+       struct platform_device *pdev = to_platform_device(sdev->dma_dev.dev);
+       struct sudmac_chan *sc;
+       struct shdma_chan *schan;
+       int err;
+
+       sc = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_chan), GFP_KERNEL);
+       if (!sc) {
+               dev_err(sdev->dma_dev.dev,
+                       "No free memory for allocating dma channels!\n");
+               return -ENOMEM;
+       }
+
+       schan = &sc->shdma_chan;
+       schan->max_xfer_len = 64 * 1024 * 1024 - 1;
+
+       shdma_chan_probe(sdev, schan, id);
+
+       sc->base = su_dev->chan_reg;
+
+       /* get platform_data */
+       sc->offset = su_dev->pdata->channel->offset;
+       if (su_dev->pdata->channel->config & SUDMAC_TX_BUFFER_MODE)
+               sc->cfg |= SUDMAC_SENDBUFM;
+       if (su_dev->pdata->channel->config & SUDMAC_RX_END_MODE)
+               sc->cfg |= SUDMAC_RCVENDM;
+       sc->cfg |= (su_dev->pdata->channel->wait << 4) & SUDMAC_LBA_WAIT;
+
+       if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH0)
+               sc->dint_end_bit |= SUDMAC_CH0ENDE;
+       if (su_dev->pdata->channel->dint_end_bit & SUDMAC_DMA_BIT_CH1)
+               sc->dint_end_bit |= SUDMAC_CH1ENDE;
+
+       /* set up channel irq */
+       if (pdev->id >= 0)
+               snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d.%d",
+                        pdev->id, id);
+       else
+               snprintf(sc->dev_id, sizeof(sc->dev_id), "sudmac%d", id);
+
+       err = shdma_request_irq(schan, irq, flags, sc->dev_id);
+       if (err) {
+               dev_err(sdev->dma_dev.dev,
+                       "DMA channel %d request_irq failed %d\n", id, err);
+               goto err_no_irq;
+       }
+
+       return 0;
+
+err_no_irq:
+       /* remove from dmaengine device node */
+       shdma_chan_remove(schan);
+       return err;
+}
+
+static void sudmac_chan_remove(struct sudmac_device *su_dev)
+{
+       struct dma_device *dma_dev = &su_dev->shdma_dev.dma_dev;
+       struct shdma_chan *schan;
+       int i;
+
+       shdma_for_each_chan(schan, &su_dev->shdma_dev, i) {
+               struct sudmac_chan *sc = to_chan(schan);
+
+               BUG_ON(!schan);
+
+               shdma_free_irq(&sc->shdma_chan);
+               shdma_chan_remove(schan);
+       }
+       dma_dev->chancnt = 0;
+}
+
+static dma_addr_t sudmac_slave_addr(struct shdma_chan *schan)
+{
+       /* SUDMAC doesn't need the address */
+       return 0;
+}
+
+static struct shdma_desc *sudmac_embedded_desc(void *buf, int i)
+{
+       return &((struct sudmac_desc *)buf)[i].shdma_desc;
+}
+
+static const struct shdma_ops sudmac_shdma_ops = {
+       .desc_completed = sudmac_desc_completed,
+       .halt_channel = sudmac_halt,
+       .channel_busy = sudmac_channel_busy,
+       .slave_addr = sudmac_slave_addr,
+       .desc_setup = sudmac_desc_setup,
+       .set_slave = sudmac_set_slave,
+       .setup_xfer = sudmac_setup_xfer,
+       .start_xfer = sudmac_start_xfer,
+       .embedded_desc = sudmac_embedded_desc,
+       .chan_irq = sudmac_chan_irq,
+       .get_partial = sudmac_get_partial,
+};
+
+static int sudmac_probe(struct platform_device *pdev)
+{
+       struct sudmac_pdata *pdata = pdev->dev.platform_data;
+       int err, i;
+       struct sudmac_device *su_dev;
+       struct dma_device *dma_dev;
+       struct resource *chan, *irq_res;
+
+       /* get platform data */
+       if (!pdata)
+               return -ENODEV;
+
+       chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+       if (!chan || !irq_res)
+               return -ENODEV;
+
+       err = -ENOMEM;
+       su_dev = devm_kzalloc(&pdev->dev, sizeof(struct sudmac_device),
+                             GFP_KERNEL);
+       if (!su_dev) {
+               dev_err(&pdev->dev, "Not enough memory\n");
+               return err;
+       }
+
+       dma_dev = &su_dev->shdma_dev.dma_dev;
+
+       su_dev->chan_reg = devm_request_and_ioremap(&pdev->dev, chan);
+       if (!su_dev->chan_reg)
+               return err;
+
+       dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
+
+       su_dev->shdma_dev.ops = &sudmac_shdma_ops;
+       su_dev->shdma_dev.desc_size = sizeof(struct sudmac_desc);
+       err = shdma_init(&pdev->dev, &su_dev->shdma_dev, pdata->channel_num);
+       if (err < 0)
+               return err;
+
+       /* platform data */
+       su_dev->pdata = pdev->dev.platform_data;
+
+       platform_set_drvdata(pdev, su_dev);
+
+       /* Create DMA Channel */
+       for (i = 0; i < pdata->channel_num; i++) {
+               err = sudmac_chan_probe(su_dev, i, irq_res->start, IRQF_SHARED);
+               if (err)
+                       goto chan_probe_err;
+       }
+
+       err = dma_async_device_register(&su_dev->shdma_dev.dma_dev);
+       if (err < 0)
+               goto chan_probe_err;
+
+       return err;
+
+chan_probe_err:
+       sudmac_chan_remove(su_dev);
+
+       platform_set_drvdata(pdev, NULL);
+       shdma_cleanup(&su_dev->shdma_dev);
+
+       return err;
+}
+
+static int sudmac_remove(struct platform_device *pdev)
+{
+       struct sudmac_device *su_dev = platform_get_drvdata(pdev);
+       struct dma_device *dma_dev = &su_dev->shdma_dev.dma_dev;
+
+       dma_async_device_unregister(dma_dev);
+       sudmac_chan_remove(su_dev);
+       shdma_cleanup(&su_dev->shdma_dev);
+       platform_set_drvdata(pdev, NULL);
+
+       return 0;
+}
+
+static struct platform_driver sudmac_driver = {
+       .driver         = {
+               .owner  = THIS_MODULE,
+               .name   = SUDMAC_DRV_NAME,
+       },
+       .probe          = sudmac_probe,
+       .remove         = sudmac_remove,
+};
+module_platform_driver(sudmac_driver);
+
+MODULE_AUTHOR("Yoshihiro Shimoda");
+MODULE_DESCRIPTION("Renesas SUDMAC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" SUDMAC_DRV_NAME);
diff --git a/include/linux/sudmac.h b/include/linux/sudmac.h
new file mode 100644 (file)
index 0000000..377b8a5
--- /dev/null
@@ -0,0 +1,52 @@
+/*
+ * Header for the SUDMAC driver
+ *
+ * Copyright (C) 2013 Renesas Solutions Corp.
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ */
+#ifndef SUDMAC_H
+#define SUDMAC_H
+
+#include <linux/dmaengine.h>
+#include <linux/shdma-base.h>
+#include <linux/types.h>
+
+/* Used by slave DMA clients to request DMA to/from a specific peripheral */
+struct sudmac_slave {
+       struct shdma_slave      shdma_slave;    /* Set by the platform */
+};
+
+/*
+ * Supplied by platforms to specify, how a DMA channel has to be configured for
+ * a certain peripheral
+ */
+struct sudmac_slave_config {
+       int             slave_id;
+};
+
+struct sudmac_channel {
+       unsigned long   offset;
+       unsigned long   config;
+       unsigned long   wait;           /* The configuable range is 0 to 3 */
+       unsigned long   dint_end_bit;
+};
+
+struct sudmac_pdata {
+       const struct sudmac_slave_config *slave;
+       int slave_num;
+       const struct sudmac_channel *channel;
+       int channel_num;
+};
+
+/* Definitions for the sudmac_channel.config */
+#define SUDMAC_TX_BUFFER_MODE  BIT(0)
+#define SUDMAC_RX_END_MODE     BIT(1)
+
+/* Definitions for the sudmac_channel.dint_end_bit */
+#define SUDMAC_DMA_BIT_CH0     BIT(0)
+#define SUDMAC_DMA_BIT_CH1     BIT(1)
+
+#endif