atmel-mci: convert to dma_request_channel and down-level dma_slave
Dan Williams [Tue, 6 Jan 2009 18:38:16 +0000 (11:38 -0700)]
dma_request_channel provides an exclusive channel, so we no longer need to
pass slave data through dmaengine.

Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

arch/avr32/include/asm/atmel-mci.h
arch/avr32/mach-at32ap/at32ap700x.c
drivers/dma/dmaengine.c
drivers/dma/dw_dmac.c
drivers/mmc/host/atmel-mci.c
include/linux/dmaengine.h
include/linux/dw_dmac.h

index 59f3fad..e5e54c6 100644 (file)
@@ -3,7 +3,7 @@
 
 #define ATMEL_MCI_MAX_NR_SLOTS 2
 
-struct dma_slave;
+#include <linux/dw_dmac.h>
 
 /**
  * struct mci_slot_pdata - board-specific per-slot configuration
@@ -28,11 +28,11 @@ struct mci_slot_pdata {
 
 /**
  * struct mci_platform_data - board-specific MMC/SDcard configuration
- * @dma_slave: DMA slave interface to use in data transfers, or NULL.
+ * @dma_slave: DMA slave interface to use in data transfers.
  * @slot: Per-slot configuration data.
  */
 struct mci_platform_data {
-       struct dma_slave        *dma_slave;
+       struct dw_dma_slave     dma_slave;
        struct mci_slot_pdata   slot[ATMEL_MCI_MAX_NR_SLOTS];
 };
 
index 066252e..414f174 100644 (file)
@@ -1305,7 +1305,7 @@ struct platform_device *__init
 at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
 {
        struct platform_device          *pdev;
-       struct dw_dma_slave             *dws;
+       struct dw_dma_slave             *dws = &data->dma_slave;
        u32                             pioa_mask;
        u32                             piob_mask;
 
@@ -1324,22 +1324,13 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
                                ARRAY_SIZE(atmel_mci0_resource)))
                goto fail;
 
-       if (data->dma_slave)
-               dws = kmemdup(to_dw_dma_slave(data->dma_slave),
-                               sizeof(struct dw_dma_slave), GFP_KERNEL);
-       else
-               dws = kzalloc(sizeof(struct dw_dma_slave), GFP_KERNEL);
-
-       dws->slave.dev = &pdev->dev;
-       dws->slave.dma_dev = &dw_dmac0_device.dev;
-       dws->slave.reg_width = DMA_SLAVE_WIDTH_32BIT;
+       dws->dma_dev = &dw_dmac0_device.dev;
+       dws->reg_width = DW_DMA_SLAVE_WIDTH_32BIT;
        dws->cfg_hi = (DWC_CFGH_SRC_PER(0)
                                | DWC_CFGH_DST_PER(1));
        dws->cfg_lo &= ~(DWC_CFGL_HS_DST_POL
                                | DWC_CFGL_HS_SRC_POL);
 
-       data->dma_slave = &dws->slave;
-
        if (platform_device_add_data(pdev, data,
                                sizeof(struct mci_platform_data)))
                goto fail;
index 7a0594f..90aca50 100644 (file)
@@ -234,10 +234,6 @@ static void dma_client_chan_alloc(struct dma_client *client)
        list_for_each_entry(device, &dma_device_list, global_node) {
                if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
                        continue;
-               /* Does the client require a specific DMA controller? */
-               if (client->slave && client->slave->dma_dev
-                               && client->slave->dma_dev != device->dev)
-                       continue;
                if (!dma_device_satisfies_mask(device, client->cap_mask))
                        continue;
 
@@ -613,10 +609,6 @@ void dma_async_client_register(struct dma_client *client)
        struct dma_chan *chan;
        int err;
 
-       /* validate client data */
-       BUG_ON(dma_has_cap(DMA_SLAVE, client->cap_mask) &&
-               !client->slave);
-
        mutex_lock(&dma_list_mutex);
        dmaengine_ref_count++;
 
index 377dafa..dbd5080 100644 (file)
@@ -567,7 +567,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
        if (unlikely(!dws || !sg_len))
                return NULL;
 
-       reg_width = dws->slave.reg_width;
+       reg_width = dws->reg_width;
        prev = first = NULL;
 
        sg_len = dma_map_sg(chan->dev.parent, sgl, sg_len, direction);
@@ -579,7 +579,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                                | DWC_CTLL_DST_FIX
                                | DWC_CTLL_SRC_INC
                                | DWC_CTLL_FC_M2P);
-               reg = dws->slave.tx_reg;
+               reg = dws->tx_reg;
                for_each_sg(sgl, sg, sg_len, i) {
                        struct dw_desc  *desc;
                        u32             len;
@@ -625,7 +625,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
                                | DWC_CTLL_SRC_FIX
                                | DWC_CTLL_FC_P2M);
 
-               reg = dws->slave.rx_reg;
+               reg = dws->rx_reg;
                for_each_sg(sgl, sg, sg_len, i) {
                        struct dw_desc  *desc;
                        u32             len;
@@ -764,7 +764,6 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan,
        struct dw_dma_chan      *dwc = to_dw_dma_chan(chan);
        struct dw_dma           *dw = to_dw_dma(chan->device);
        struct dw_desc          *desc;
-       struct dma_slave        *slave;
        struct dw_dma_slave     *dws;
        int                     i;
        u32                     cfghi;
@@ -772,12 +771,6 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan,
 
        dev_vdbg(&chan->dev, "alloc_chan_resources\n");
 
-       /* Channels doing slave DMA can only handle one client. */
-       if (dwc->dws || (client && client->slave)) {
-               if (chan->client_count)
-                       return -EBUSY;
-       }
-
        /* ASSERT:  channel is idle */
        if (dma_readl(dw, CH_EN) & dwc->mask) {
                dev_dbg(&chan->dev, "DMA channel not idle?\n");
@@ -789,23 +782,17 @@ static int dwc_alloc_chan_resources(struct dma_chan *chan,
        cfghi = DWC_CFGH_FIFO_MODE;
        cfglo = 0;
 
-       slave = client->slave;
-       if (slave) {
+       dws = dwc->dws;
+       if (dws) {
                /*
                 * We need controller-specific data to set up slave
                 * transfers.
                 */
-               BUG_ON(!slave->dma_dev || slave->dma_dev != dw->dma.dev);
-
-               dws = container_of(slave, struct dw_dma_slave, slave);
+               BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev);
 
-               dwc->dws = dws;
                cfghi = dws->cfg_hi;
                cfglo = dws->cfg_lo;
-       } else {
-               dwc->dws = NULL;
        }
-
        channel_writel(dwc, CFG_LO, cfglo);
        channel_writel(dwc, CFG_HI, cfghi);
 
index 6c11f4d..7a34118 100644 (file)
@@ -1441,60 +1441,6 @@ static irqreturn_t atmci_detect_interrupt(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-#ifdef CONFIG_MMC_ATMELMCI_DMA
-
-static inline struct atmel_mci *
-dma_client_to_atmel_mci(struct dma_client *client)
-{
-       return container_of(client, struct atmel_mci, dma.client);
-}
-
-static enum dma_state_client atmci_dma_event(struct dma_client *client,
-               struct dma_chan *chan, enum dma_state state)
-{
-       struct atmel_mci        *host;
-       enum dma_state_client   ret = DMA_NAK;
-
-       host = dma_client_to_atmel_mci(client);
-
-       switch (state) {
-       case DMA_RESOURCE_AVAILABLE:
-               spin_lock_bh(&host->lock);
-               if (!host->dma.chan) {
-                       host->dma.chan = chan;
-                       ret = DMA_ACK;
-               }
-               spin_unlock_bh(&host->lock);
-
-               if (ret == DMA_ACK)
-                       dev_info(&host->pdev->dev,
-                                       "Using %s for DMA transfers\n",
-                                       chan->dev.bus_id);
-               break;
-
-       case DMA_RESOURCE_REMOVED:
-               spin_lock_bh(&host->lock);
-               if (host->dma.chan == chan) {
-                       host->dma.chan = NULL;
-                       ret = DMA_ACK;
-               }
-               spin_unlock_bh(&host->lock);
-
-               if (ret == DMA_ACK)
-                       dev_info(&host->pdev->dev,
-                                       "Lost %s, falling back to PIO\n",
-                                       chan->dev.bus_id);
-               break;
-
-       default:
-               break;
-       }
-
-
-       return ret;
-}
-#endif /* CONFIG_MMC_ATMELMCI_DMA */
-
 static int __init atmci_init_slot(struct atmel_mci *host,
                struct mci_slot_pdata *slot_data, unsigned int id,
                u32 sdc_reg)
@@ -1598,6 +1544,18 @@ static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
        mmc_free_host(slot->mmc);
 }
 
+#ifdef CONFIG_MMC_ATMELMCI_DMA
+static enum dma_state_client filter(struct dma_chan *chan, void *slave)
+{
+       struct dw_dma_slave *dws = slave;
+
+       if (dws->dma_dev == chan->device->dev)
+               return DMA_ACK;
+       else
+               return DMA_DUP;
+}
+#endif
+
 static int __init atmci_probe(struct platform_device *pdev)
 {
        struct mci_platform_data        *pdata;
@@ -1650,22 +1608,20 @@ static int __init atmci_probe(struct platform_device *pdev)
                goto err_request_irq;
 
 #ifdef CONFIG_MMC_ATMELMCI_DMA
-       if (pdata->dma_slave) {
-               struct dma_slave *slave = pdata->dma_slave;
+       if (pdata->dma_slave.dma_dev) {
+               struct dw_dma_slave *dws = &pdata->dma_slave;
+               dma_cap_mask_t mask;
 
-               slave->tx_reg = regs->start + MCI_TDR;
-               slave->rx_reg = regs->start + MCI_RDR;
+               dws->tx_reg = regs->start + MCI_TDR;
+               dws->rx_reg = regs->start + MCI_RDR;
 
                /* Try to grab a DMA channel */
-               host->dma.client.event_callback = atmci_dma_event;
-               dma_cap_set(DMA_SLAVE, host->dma.client.cap_mask);
-               host->dma.client.slave = slave;
-
-               dma_async_client_register(&host->dma.client);
-               dma_async_client_chan_request(&host->dma.client);
-       } else {
-               dev_notice(&pdev->dev, "DMA not available, using PIO\n");
+               dma_cap_zero(mask);
+               dma_cap_set(DMA_SLAVE, mask);
+               host->dma.chan = dma_request_channel(mask, filter, dws);
        }
+       if (!host->dma.chan)
+               dev_notice(&pdev->dev, "DMA not available, using PIO\n");
 #endif /* CONFIG_MMC_ATMELMCI_DMA */
 
        platform_set_drvdata(pdev, host);
@@ -1697,8 +1653,8 @@ static int __init atmci_probe(struct platform_device *pdev)
 
 err_init_slot:
 #ifdef CONFIG_MMC_ATMELMCI_DMA
-       if (pdata->dma_slave)
-               dma_async_client_unregister(&host->dma.client);
+       if (host->dma.chan)
+               dma_release_channel(host->dma.chan);
 #endif
        free_irq(irq, host);
 err_request_irq:
@@ -1729,8 +1685,8 @@ static int __exit atmci_remove(struct platform_device *pdev)
        clk_disable(host->mck);
 
 #ifdef CONFIG_MMC_ATMELMCI_DMA
-       if (host->dma.client.slave)
-               dma_async_client_unregister(&host->dma.client);
+       if (host->dma.chan)
+               dma_release_channel(host->dma.chan);
 #endif
 
        free_irq(platform_get_irq(pdev, 0), host);
@@ -1759,7 +1715,7 @@ static void __exit atmci_exit(void)
        platform_driver_unregister(&atmci_driver);
 }
 
-module_init(atmci_init);
+late_initcall(atmci_init); /* try to load after dma driver when built-in */
 module_exit(atmci_exit);
 
 MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
index 6f2d070..d63544c 100644 (file)
@@ -96,17 +96,6 @@ enum dma_transaction_type {
 /* last transaction type for creation of the capabilities mask */
 #define DMA_TX_TYPE_END (DMA_SLAVE + 1)
 
-/**
- * enum dma_slave_width - DMA slave register access width.
- * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
- * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
- * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
- */
-enum dma_slave_width {
-       DMA_SLAVE_WIDTH_8BIT,
-       DMA_SLAVE_WIDTH_16BIT,
-       DMA_SLAVE_WIDTH_32BIT,
-};
 
 /**
  * enum dma_ctrl_flags - DMA flags to augment operation preparation,
@@ -133,32 +122,6 @@ enum dma_ctrl_flags {
 typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
 
 /**
- * struct dma_slave - Information about a DMA slave
- * @dev: device acting as DMA slave
- * @dma_dev: required DMA master device. If non-NULL, the client can not be
- *     bound to other masters than this.
- * @tx_reg: physical address of data register used for
- *     memory-to-peripheral transfers
- * @rx_reg: physical address of data register used for
- *     peripheral-to-memory transfers
- * @reg_width: peripheral register width
- *
- * If dma_dev is non-NULL, the client can not be bound to other DMA
- * masters than the one corresponding to this device. The DMA master
- * driver may use this to determine if there is controller-specific
- * data wrapped around this struct. Drivers of platform code that sets
- * the dma_dev field must therefore make sure to use an appropriate
- * controller-specific dma slave structure wrapping this struct.
- */
-struct dma_slave {
-       struct device           *dev;
-       struct device           *dma_dev;
-       dma_addr_t              tx_reg;
-       dma_addr_t              rx_reg;
-       enum dma_slave_width    reg_width;
-};
-
-/**
  * struct dma_chan_percpu - the per-CPU part of struct dma_chan
  * @refcount: local_t used for open-coded "bigref" counting
  * @memcpy_count: transaction counter
@@ -248,7 +211,6 @@ typedef enum dma_state_client (*dma_filter_fn)(struct dma_chan *chan, void *filt
 struct dma_client {
        dma_event_callback      event_callback;
        dma_cap_mask_t          cap_mask;
-       struct dma_slave        *slave;
        struct list_head        global_node;
 };
 
index 04d217b..d797dde 100644 (file)
@@ -22,14 +22,34 @@ struct dw_dma_platform_data {
 };
 
 /**
+ * enum dw_dma_slave_width - DMA slave register access width.
+ * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
+ */
+enum dw_dma_slave_width {
+       DW_DMA_SLAVE_WIDTH_8BIT,
+       DW_DMA_SLAVE_WIDTH_16BIT,
+       DW_DMA_SLAVE_WIDTH_32BIT,
+};
+
+/**
  * struct dw_dma_slave - Controller-specific information about a slave
- * @slave: Generic information about the slave
- * @ctl_lo: Platform-specific initializer for the CTL_LO register
+ *
+ * @dma_dev: required DMA master device
+ * @tx_reg: physical address of data register used for
+ *     memory-to-peripheral transfers
+ * @rx_reg: physical address of data register used for
+ *     peripheral-to-memory transfers
+ * @reg_width: peripheral register width
  * @cfg_hi: Platform-specific initializer for the CFG_HI register
  * @cfg_lo: Platform-specific initializer for the CFG_LO register
  */
 struct dw_dma_slave {
-       struct dma_slave        slave;
+       struct device           *dma_dev;
+       dma_addr_t              tx_reg;
+       dma_addr_t              rx_reg;
+       enum dw_dma_slave_width reg_width;
        u32                     cfg_hi;
        u32                     cfg_lo;
 };
@@ -54,9 +74,4 @@ struct dw_dma_slave {
 #define DWC_CFGL_HS_DST_POL    (1 << 18)       /* dst handshake active low */
 #define DWC_CFGL_HS_SRC_POL    (1 << 19)       /* src handshake active low */
 
-static inline struct dw_dma_slave *to_dw_dma_slave(struct dma_slave *slave)
-{
-       return container_of(slave, struct dw_dma_slave, slave);
-}
-
 #endif /* DW_DMAC_H */