v4.19.13 snapshot.
diff --git a/drivers/dma/hsu/Kconfig b/drivers/dma/hsu/Kconfig
new file mode 100644
index 0000000..c708417
--- /dev/null
+++ b/drivers/dma/hsu/Kconfig
@@ -0,0 +1,9 @@
+# DMA engine configuration for hsu
+config HSU_DMA
+ tristate
+ select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
+
+config HSU_DMA_PCI
+ tristate
+ depends on HSU_DMA && PCI
diff --git a/drivers/dma/hsu/Makefile b/drivers/dma/hsu/Makefile
new file mode 100644
index 0000000..b8f9af0
--- /dev/null
+++ b/drivers/dma/hsu/Makefile
@@ -0,0 +1,5 @@
+obj-$(CONFIG_HSU_DMA) += hsu_dma.o
+hsu_dma-objs := hsu.o
+
+obj-$(CONFIG_HSU_DMA_PCI) += hsu_dma_pci.o
+hsu_dma_pci-objs := pci.o
diff --git a/drivers/dma/hsu/hsu.c b/drivers/dma/hsu/hsu.c
new file mode 100644
index 0000000..202ffa9
--- /dev/null
+++ b/drivers/dma/hsu/hsu.c
@@ -0,0 +1,508 @@
+/*
+ * Core driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ *
+ * 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.
+ */
+
+/*
+ * DMA channel allocation:
+ * 1. Even number chans are used for DMA Read (UART TX), odd chans for DMA
+ * Write (UART RX).
+ * 2. 0/1 channel are assigned to port 0, 2/3 chan to port 1, 4/5 chan to
+ * port 3, and so on.
+ */
+
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "hsu.h"
+
+#define HSU_DMA_BUSWIDTHS \
+ BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
+ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_8_BYTES) | \
+ BIT(DMA_SLAVE_BUSWIDTH_16_BYTES)
+
+static inline void hsu_chan_disable(struct hsu_dma_chan *hsuc)
+{
+ hsu_chan_writel(hsuc, HSU_CH_CR, 0);
+}
+
+static inline void hsu_chan_enable(struct hsu_dma_chan *hsuc)
+{
+ u32 cr = HSU_CH_CR_CHA;
+
+ if (hsuc->direction == DMA_MEM_TO_DEV)
+ cr &= ~HSU_CH_CR_CHD;
+ else if (hsuc->direction == DMA_DEV_TO_MEM)
+ cr |= HSU_CH_CR_CHD;
+
+ hsu_chan_writel(hsuc, HSU_CH_CR, cr);
+}
+
+static void hsu_dma_chan_start(struct hsu_dma_chan *hsuc)
+{
+ struct dma_slave_config *config = &hsuc->config;
+ struct hsu_dma_desc *desc = hsuc->desc;
+ u32 bsr = 0, mtsr = 0; /* to shut the compiler up */
+ u32 dcr = HSU_CH_DCR_CHSOE | HSU_CH_DCR_CHEI;
+ unsigned int i, count;
+
+ if (hsuc->direction == DMA_MEM_TO_DEV) {
+ bsr = config->dst_maxburst;
+ mtsr = config->src_addr_width;
+ } else if (hsuc->direction == DMA_DEV_TO_MEM) {
+ bsr = config->src_maxburst;
+ mtsr = config->dst_addr_width;
+ }
+
+ hsu_chan_disable(hsuc);
+
+ hsu_chan_writel(hsuc, HSU_CH_DCR, 0);
+ hsu_chan_writel(hsuc, HSU_CH_BSR, bsr);
+ hsu_chan_writel(hsuc, HSU_CH_MTSR, mtsr);
+
+ /* Set descriptors */
+ count = desc->nents - desc->active;
+ for (i = 0; i < count && i < HSU_DMA_CHAN_NR_DESC; i++) {
+ hsu_chan_writel(hsuc, HSU_CH_DxSAR(i), desc->sg[i].addr);
+ hsu_chan_writel(hsuc, HSU_CH_DxTSR(i), desc->sg[i].len);
+
+ /* Prepare value for DCR */
+ dcr |= HSU_CH_DCR_DESCA(i);
+ dcr |= HSU_CH_DCR_CHTOI(i); /* timeout bit, see HSU Errata 1 */
+
+ desc->active++;
+ }
+ /* Only for the last descriptor in the chain */
+ dcr |= HSU_CH_DCR_CHSOD(count - 1);
+ dcr |= HSU_CH_DCR_CHDI(count - 1);
+
+ hsu_chan_writel(hsuc, HSU_CH_DCR, dcr);
+
+ hsu_chan_enable(hsuc);
+}
+
+static void hsu_dma_stop_channel(struct hsu_dma_chan *hsuc)
+{
+ hsu_chan_disable(hsuc);
+ hsu_chan_writel(hsuc, HSU_CH_DCR, 0);
+}
+
+static void hsu_dma_start_channel(struct hsu_dma_chan *hsuc)
+{
+ hsu_dma_chan_start(hsuc);
+}
+
+static void hsu_dma_start_transfer(struct hsu_dma_chan *hsuc)
+{
+ struct virt_dma_desc *vdesc;
+
+ /* Get the next descriptor */
+ vdesc = vchan_next_desc(&hsuc->vchan);
+ if (!vdesc) {
+ hsuc->desc = NULL;
+ return;
+ }
+
+ list_del(&vdesc->node);
+ hsuc->desc = to_hsu_dma_desc(vdesc);
+
+ /* Start the channel with a new descriptor */
+ hsu_dma_start_channel(hsuc);
+}
+
+/*
+ * hsu_dma_get_status() - get DMA channel status
+ * @chip: HSUART DMA chip
+ * @nr: DMA channel number
+ * @status: pointer for DMA Channel Status Register value
+ *
+ * Description:
+ * The function reads and clears the DMA Channel Status Register, checks
+ * if it was a timeout interrupt and returns a corresponding value.
+ *
+ * Caller should provide a valid pointer for the DMA Channel Status
+ * Register value that will be returned in @status.
+ *
+ * Return:
+ * 1 for DMA timeout status, 0 for other DMA status, or error code for
+ * invalid parameters or no interrupt pending.
+ */
+int hsu_dma_get_status(struct hsu_dma_chip *chip, unsigned short nr,
+ u32 *status)
+{
+ struct hsu_dma_chan *hsuc;
+ unsigned long flags;
+ u32 sr;
+
+ /* Sanity check */
+ if (nr >= chip->hsu->nr_channels)
+ return -EINVAL;
+
+ hsuc = &chip->hsu->chan[nr];
+
+ /*
+ * No matter what situation, need read clear the IRQ status
+ * There is a bug, see Errata 5, HSD 2900918
+ */
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ sr = hsu_chan_readl(hsuc, HSU_CH_SR);
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+ /* Check if any interrupt is pending */
+ sr &= ~(HSU_CH_SR_DESCE_ANY | HSU_CH_SR_CDESC_ANY);
+ if (!sr)
+ return -EIO;
+
+ /* Timeout IRQ, need wait some time, see Errata 2 */
+ if (sr & HSU_CH_SR_DESCTO_ANY)
+ udelay(2);
+
+ /*
+ * At this point, at least one of Descriptor Time Out, Channel Error
+ * or Descriptor Done bits must be set. Clear the Descriptor Time Out
+ * bits and if sr is still non-zero, it must be channel error or
+ * descriptor done which are higher priority than timeout and handled
+ * in hsu_dma_do_irq(). Else, it must be a timeout.
+ */
+ sr &= ~HSU_CH_SR_DESCTO_ANY;
+
+ *status = sr;
+
+ return sr ? 0 : 1;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_get_status);
+
+/*
+ * hsu_dma_do_irq() - DMA interrupt handler
+ * @chip: HSUART DMA chip
+ * @nr: DMA channel number
+ * @status: Channel Status Register value
+ *
+ * Description:
+ * This function handles Channel Error and Descriptor Done interrupts.
+ * This function should be called after determining that the DMA interrupt
+ * is not a normal timeout interrupt, ie. hsu_dma_get_status() returned 0.
+ *
+ * Return:
+ * 0 for invalid channel number, 1 otherwise.
+ */
+int hsu_dma_do_irq(struct hsu_dma_chip *chip, unsigned short nr, u32 status)
+{
+ struct hsu_dma_chan *hsuc;
+ struct hsu_dma_desc *desc;
+ unsigned long flags;
+
+ /* Sanity check */
+ if (nr >= chip->hsu->nr_channels)
+ return 0;
+
+ hsuc = &chip->hsu->chan[nr];
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ desc = hsuc->desc;
+ if (desc) {
+ if (status & HSU_CH_SR_CHE) {
+ desc->status = DMA_ERROR;
+ } else if (desc->active < desc->nents) {
+ hsu_dma_start_channel(hsuc);
+ } else {
+ vchan_cookie_complete(&desc->vdesc);
+ desc->status = DMA_COMPLETE;
+ hsu_dma_start_transfer(hsuc);
+ }
+ }
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_do_irq);
+
+static struct hsu_dma_desc *hsu_dma_alloc_desc(unsigned int nents)
+{
+ struct hsu_dma_desc *desc;
+
+ desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
+ if (!desc)
+ return NULL;
+
+ desc->sg = kcalloc(nents, sizeof(*desc->sg), GFP_NOWAIT);
+ if (!desc->sg) {
+ kfree(desc);
+ return NULL;
+ }
+
+ return desc;
+}
+
+static void hsu_dma_desc_free(struct virt_dma_desc *vdesc)
+{
+ struct hsu_dma_desc *desc = to_hsu_dma_desc(vdesc);
+
+ kfree(desc->sg);
+ kfree(desc);
+}
+
+static struct dma_async_tx_descriptor *hsu_dma_prep_slave_sg(
+ struct dma_chan *chan, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction direction,
+ unsigned long flags, void *context)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ struct hsu_dma_desc *desc;
+ struct scatterlist *sg;
+ unsigned int i;
+
+ desc = hsu_dma_alloc_desc(sg_len);
+ if (!desc)
+ return NULL;
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ desc->sg[i].addr = sg_dma_address(sg);
+ desc->sg[i].len = sg_dma_len(sg);
+
+ desc->length += sg_dma_len(sg);
+ }
+
+ desc->nents = sg_len;
+ desc->direction = direction;
+ /* desc->active = 0 by kzalloc */
+ desc->status = DMA_IN_PROGRESS;
+
+ return vchan_tx_prep(&hsuc->vchan, &desc->vdesc, flags);
+}
+
+static void hsu_dma_issue_pending(struct dma_chan *chan)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ if (vchan_issue_pending(&hsuc->vchan) && !hsuc->desc)
+ hsu_dma_start_transfer(hsuc);
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+}
+
+static size_t hsu_dma_active_desc_size(struct hsu_dma_chan *hsuc)
+{
+ struct hsu_dma_desc *desc = hsuc->desc;
+ size_t bytes = 0;
+ int i;
+
+ for (i = desc->active; i < desc->nents; i++)
+ bytes += desc->sg[i].len;
+
+ i = HSU_DMA_CHAN_NR_DESC - 1;
+ do {
+ bytes += hsu_chan_readl(hsuc, HSU_CH_DxTSR(i));
+ } while (--i >= 0);
+
+ return bytes;
+}
+
+static enum dma_status hsu_dma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie, struct dma_tx_state *state)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ struct virt_dma_desc *vdesc;
+ enum dma_status status;
+ size_t bytes;
+ unsigned long flags;
+
+ status = dma_cookie_status(chan, cookie, state);
+ if (status == DMA_COMPLETE)
+ return status;
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ vdesc = vchan_find_desc(&hsuc->vchan, cookie);
+ if (hsuc->desc && cookie == hsuc->desc->vdesc.tx.cookie) {
+ bytes = hsu_dma_active_desc_size(hsuc);
+ dma_set_residue(state, bytes);
+ status = hsuc->desc->status;
+ } else if (vdesc) {
+ bytes = to_hsu_dma_desc(vdesc)->length;
+ dma_set_residue(state, bytes);
+ }
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+ return status;
+}
+
+static int hsu_dma_slave_config(struct dma_chan *chan,
+ struct dma_slave_config *config)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+
+ /* Check if chan will be configured for slave transfers */
+ if (!is_slave_direction(config->direction))
+ return -EINVAL;
+
+ memcpy(&hsuc->config, config, sizeof(hsuc->config));
+
+ return 0;
+}
+
+static int hsu_dma_pause(struct dma_chan *chan)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ if (hsuc->desc && hsuc->desc->status == DMA_IN_PROGRESS) {
+ hsu_chan_disable(hsuc);
+ hsuc->desc->status = DMA_PAUSED;
+ }
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+ return 0;
+}
+
+static int hsu_dma_resume(struct dma_chan *chan)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+ if (hsuc->desc && hsuc->desc->status == DMA_PAUSED) {
+ hsuc->desc->status = DMA_IN_PROGRESS;
+ hsu_chan_enable(hsuc);
+ }
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+
+ return 0;
+}
+
+static int hsu_dma_terminate_all(struct dma_chan *chan)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+ unsigned long flags;
+ LIST_HEAD(head);
+
+ spin_lock_irqsave(&hsuc->vchan.lock, flags);
+
+ hsu_dma_stop_channel(hsuc);
+ if (hsuc->desc) {
+ hsu_dma_desc_free(&hsuc->desc->vdesc);
+ hsuc->desc = NULL;
+ }
+
+ vchan_get_all_descriptors(&hsuc->vchan, &head);
+ spin_unlock_irqrestore(&hsuc->vchan.lock, flags);
+ vchan_dma_desc_free_list(&hsuc->vchan, &head);
+
+ return 0;
+}
+
+static void hsu_dma_free_chan_resources(struct dma_chan *chan)
+{
+ vchan_free_chan_resources(to_virt_chan(chan));
+}
+
+static void hsu_dma_synchronize(struct dma_chan *chan)
+{
+ struct hsu_dma_chan *hsuc = to_hsu_dma_chan(chan);
+
+ vchan_synchronize(&hsuc->vchan);
+}
+
+int hsu_dma_probe(struct hsu_dma_chip *chip)
+{
+ struct hsu_dma *hsu;
+ void __iomem *addr = chip->regs + chip->offset;
+ unsigned short i;
+ int ret;
+
+ hsu = devm_kzalloc(chip->dev, sizeof(*hsu), GFP_KERNEL);
+ if (!hsu)
+ return -ENOMEM;
+
+ chip->hsu = hsu;
+
+ /* Calculate nr_channels from the IO space length */
+ hsu->nr_channels = (chip->length - chip->offset) / HSU_DMA_CHAN_LENGTH;
+
+ hsu->chan = devm_kcalloc(chip->dev, hsu->nr_channels,
+ sizeof(*hsu->chan), GFP_KERNEL);
+ if (!hsu->chan)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&hsu->dma.channels);
+ for (i = 0; i < hsu->nr_channels; i++) {
+ struct hsu_dma_chan *hsuc = &hsu->chan[i];
+
+ hsuc->vchan.desc_free = hsu_dma_desc_free;
+ vchan_init(&hsuc->vchan, &hsu->dma);
+
+ hsuc->direction = (i & 0x1) ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
+ hsuc->reg = addr + i * HSU_DMA_CHAN_LENGTH;
+ }
+
+ dma_cap_set(DMA_SLAVE, hsu->dma.cap_mask);
+ dma_cap_set(DMA_PRIVATE, hsu->dma.cap_mask);
+
+ hsu->dma.device_free_chan_resources = hsu_dma_free_chan_resources;
+
+ hsu->dma.device_prep_slave_sg = hsu_dma_prep_slave_sg;
+
+ hsu->dma.device_issue_pending = hsu_dma_issue_pending;
+ hsu->dma.device_tx_status = hsu_dma_tx_status;
+
+ hsu->dma.device_config = hsu_dma_slave_config;
+ hsu->dma.device_pause = hsu_dma_pause;
+ hsu->dma.device_resume = hsu_dma_resume;
+ hsu->dma.device_terminate_all = hsu_dma_terminate_all;
+ hsu->dma.device_synchronize = hsu_dma_synchronize;
+
+ hsu->dma.src_addr_widths = HSU_DMA_BUSWIDTHS;
+ hsu->dma.dst_addr_widths = HSU_DMA_BUSWIDTHS;
+ hsu->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+ hsu->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+ hsu->dma.dev = chip->dev;
+
+ dma_set_max_seg_size(hsu->dma.dev, HSU_CH_DxTSR_MASK);
+
+ ret = dma_async_device_register(&hsu->dma);
+ if (ret)
+ return ret;
+
+ dev_info(chip->dev, "Found HSU DMA, %d channels\n", hsu->nr_channels);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_probe);
+
+int hsu_dma_remove(struct hsu_dma_chip *chip)
+{
+ struct hsu_dma *hsu = chip->hsu;
+ unsigned short i;
+
+ dma_async_device_unregister(&hsu->dma);
+
+ for (i = 0; i < hsu->nr_channels; i++) {
+ struct hsu_dma_chan *hsuc = &hsu->chan[i];
+
+ tasklet_kill(&hsuc->vchan.task);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hsu_dma_remove);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA core driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
diff --git a/drivers/dma/hsu/hsu.h b/drivers/dma/hsu/hsu.h
new file mode 100644
index 0000000..486b023
--- /dev/null
+++ b/drivers/dma/hsu/hsu.h
@@ -0,0 +1,126 @@
+/*
+ * Driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ *
+ * 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 __DMA_HSU_H__
+#define __DMA_HSU_H__
+
+#include <linux/spinlock.h>
+#include <linux/dma/hsu.h>
+
+#include "../virt-dma.h"
+
+#define HSU_CH_SR 0x00 /* channel status */
+#define HSU_CH_CR 0x04 /* channel control */
+#define HSU_CH_DCR 0x08 /* descriptor control */
+#define HSU_CH_BSR 0x10 /* FIFO buffer size */
+#define HSU_CH_MTSR 0x14 /* minimum transfer size */
+#define HSU_CH_DxSAR(x) (0x20 + 8 * (x)) /* desc start addr */
+#define HSU_CH_DxTSR(x) (0x24 + 8 * (x)) /* desc transfer size */
+#define HSU_CH_D0SAR 0x20 /* desc 0 start addr */
+#define HSU_CH_D0TSR 0x24 /* desc 0 transfer size */
+#define HSU_CH_D1SAR 0x28
+#define HSU_CH_D1TSR 0x2c
+#define HSU_CH_D2SAR 0x30
+#define HSU_CH_D2TSR 0x34
+#define HSU_CH_D3SAR 0x38
+#define HSU_CH_D3TSR 0x3c
+
+#define HSU_DMA_CHAN_NR_DESC 4
+#define HSU_DMA_CHAN_LENGTH 0x40
+
+/* Bits in HSU_CH_SR */
+#define HSU_CH_SR_DESCTO(x) BIT(8 + (x))
+#define HSU_CH_SR_DESCTO_ANY (BIT(11) | BIT(10) | BIT(9) | BIT(8))
+#define HSU_CH_SR_CHE BIT(15)
+#define HSU_CH_SR_DESCE(x) BIT(16 + (x))
+#define HSU_CH_SR_DESCE_ANY (BIT(19) | BIT(18) | BIT(17) | BIT(16))
+#define HSU_CH_SR_CDESC_ANY (BIT(31) | BIT(30))
+
+/* Bits in HSU_CH_CR */
+#define HSU_CH_CR_CHA BIT(0)
+#define HSU_CH_CR_CHD BIT(1)
+
+/* Bits in HSU_CH_DCR */
+#define HSU_CH_DCR_DESCA(x) BIT(0 + (x))
+#define HSU_CH_DCR_CHSOD(x) BIT(8 + (x))
+#define HSU_CH_DCR_CHSOTO BIT(14)
+#define HSU_CH_DCR_CHSOE BIT(15)
+#define HSU_CH_DCR_CHDI(x) BIT(16 + (x))
+#define HSU_CH_DCR_CHEI BIT(23)
+#define HSU_CH_DCR_CHTOI(x) BIT(24 + (x))
+
+/* Bits in HSU_CH_DxTSR */
+#define HSU_CH_DxTSR_MASK GENMASK(15, 0)
+#define HSU_CH_DxTSR_TSR(x) ((x) & HSU_CH_DxTSR_MASK)
+
+struct hsu_dma_sg {
+ dma_addr_t addr;
+ unsigned int len;
+};
+
+struct hsu_dma_desc {
+ struct virt_dma_desc vdesc;
+ enum dma_transfer_direction direction;
+ struct hsu_dma_sg *sg;
+ unsigned int nents;
+ size_t length;
+ unsigned int active;
+ enum dma_status status;
+};
+
+static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
+{
+ return container_of(vdesc, struct hsu_dma_desc, vdesc);
+}
+
+struct hsu_dma_chan {
+ struct virt_dma_chan vchan;
+
+ void __iomem *reg;
+
+ /* hardware configuration */
+ enum dma_transfer_direction direction;
+ struct dma_slave_config config;
+
+ struct hsu_dma_desc *desc;
+};
+
+static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct hsu_dma_chan, vchan.chan);
+}
+
+static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
+{
+ return readl(hsuc->reg + offset);
+}
+
+static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
+ u32 value)
+{
+ writel(value, hsuc->reg + offset);
+}
+
+struct hsu_dma {
+ struct dma_device dma;
+
+ /* channels */
+ struct hsu_dma_chan *chan;
+ unsigned short nr_channels;
+};
+
+static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
+{
+ return container_of(ddev, struct hsu_dma, dma);
+}
+
+#endif /* __DMA_HSU_H__ */
diff --git a/drivers/dma/hsu/pci.c b/drivers/dma/hsu/pci.c
new file mode 100644
index 0000000..ad45cd3
--- /dev/null
+++ b/drivers/dma/hsu/pci.c
@@ -0,0 +1,146 @@
+/*
+ * PCI driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ *
+ * 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.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "hsu.h"
+
+#define HSU_PCI_DMASR 0x00
+#define HSU_PCI_DMAISR 0x04
+
+#define HSU_PCI_CHAN_OFFSET 0x100
+
+#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA 0x081e
+#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA 0x1192
+
+static irqreturn_t hsu_pci_irq(int irq, void *dev)
+{
+ struct hsu_dma_chip *chip = dev;
+ struct pci_dev *pdev = to_pci_dev(chip->dev);
+ u32 dmaisr;
+ u32 status;
+ unsigned short i;
+ int ret = 0;
+ int err;
+
+ /*
+ * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
+ * to have different numbers, is shared between HSU DMA and UART IPs.
+ * Thus on such SoCs we are expecting that IRQ handler is called in
+ * UART driver only.
+ */
+ if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
+ return IRQ_HANDLED;
+
+ dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
+ for (i = 0; i < chip->hsu->nr_channels; i++) {
+ if (dmaisr & 0x1) {
+ err = hsu_dma_get_status(chip, i, &status);
+ if (err > 0)
+ ret |= 1;
+ else if (err == 0)
+ ret |= hsu_dma_do_irq(chip, i, status);
+ }
+ dmaisr >>= 1;
+ }
+
+ return IRQ_RETVAL(ret);
+}
+
+static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct hsu_dma_chip *chip;
+ int ret;
+
+ ret = pcim_enable_device(pdev);
+ if (ret)
+ return ret;
+
+ ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
+ if (ret) {
+ dev_err(&pdev->dev, "I/O memory remapping failed\n");
+ return ret;
+ }
+
+ pci_set_master(pdev);
+ pci_try_set_mwi(pdev);
+
+ ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (ret)
+ return ret;
+
+ ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (ret)
+ return ret;
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+ if (ret < 0)
+ return ret;
+
+ chip->dev = &pdev->dev;
+ chip->regs = pcim_iomap_table(pdev)[0];
+ chip->length = pci_resource_len(pdev, 0);
+ chip->offset = HSU_PCI_CHAN_OFFSET;
+ chip->irq = pci_irq_vector(pdev, 0);
+
+ ret = hsu_dma_probe(chip);
+ if (ret)
+ return ret;
+
+ ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
+ if (ret)
+ goto err_register_irq;
+
+ pci_set_drvdata(pdev, chip);
+
+ return 0;
+
+err_register_irq:
+ hsu_dma_remove(chip);
+ return ret;
+}
+
+static void hsu_pci_remove(struct pci_dev *pdev)
+{
+ struct hsu_dma_chip *chip = pci_get_drvdata(pdev);
+
+ free_irq(chip->irq, chip);
+ hsu_dma_remove(chip);
+}
+
+static const struct pci_device_id hsu_pci_id_table[] = {
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
+
+static struct pci_driver hsu_pci_driver = {
+ .name = "hsu_dma_pci",
+ .id_table = hsu_pci_id_table,
+ .probe = hsu_pci_probe,
+ .remove = hsu_pci_remove,
+};
+
+module_pci_driver(hsu_pci_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");