#include <linux/completion.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mtd/cfi.h>
#include <linux/mtd/hyperbus.h>
#include <linux/mtd/mtd.h>
#include <linux/mux/consumer.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/sched/task_stack.h>
#include <linux/types.h>
#define AM654_HBMC_CALIB_COUNT 25
struct am654_hbmc_device_priv {
struct completion rx_dma_complete;
phys_addr_t device_base;
struct hyperbus_ctlr *ctlr;
struct dma_chan *rx_chan;
};
struct am654_hbmc_priv {
struct hyperbus_ctlr ctlr;
struct hyperbus_device hbdev;
struct mux_control *mux_ctrl;
};
static int am654_hbmc_calibrate(struct hyperbus_device *hbdev)
{
struct map_info *map = &hbdev->map;
struct cfi_private cfi;
int count = AM654_HBMC_CALIB_COUNT;
int pass_count = 0;
int ret;
cfi.interleave = 1;
cfi.device_type = CFI_DEVICETYPE_X16;
cfi_send_gen_cmd(0xF0, 0, 0, map, &cfi, cfi.device_type, NULL);
cfi_send_gen_cmd(0x98, 0x55, 0, map, &cfi, cfi.device_type, NULL);
while (count--) {
ret = cfi_qry_present(map, 0, &cfi);
if (ret)
pass_count++;
else
pass_count = 0;
if (pass_count == 5)
break;
}
cfi_qry_mode_off(0, map, &cfi);
return ret;
}
static void am654_hbmc_dma_callback(void *param)
{
struct am654_hbmc_device_priv *priv = param;
complete(&priv->rx_dma_complete);
}
static int am654_hbmc_dma_read(struct am654_hbmc_device_priv *priv, void *to,
unsigned long from, ssize_t len)
{
enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
struct dma_chan *rx_chan = priv->rx_chan;
struct dma_async_tx_descriptor *tx;
dma_addr_t dma_dst, dma_src;
dma_cookie_t cookie;
int ret;
if (!priv->rx_chan || !virt_addr_valid(to) || object_is_on_stack(to))
return -EINVAL;
dma_dst = dma_map_single(rx_chan->device->dev, to, len, DMA_FROM_DEVICE);
if (dma_mapping_error(rx_chan->device->dev, dma_dst)) {
dev_dbg(priv->ctlr->dev, "DMA mapping failed\n");
return -EIO;
}
dma_src = priv->device_base + from;
tx = dmaengine_prep_dma_memcpy(rx_chan, dma_dst, dma_src, len, flags);
if (!tx) {
dev_err(priv->ctlr->dev, "device_prep_dma_memcpy error\n");
ret = -EIO;
goto unmap_dma;
}
reinit_completion(&priv->rx_dma_complete);
tx->callback = am654_hbmc_dma_callback;
tx->callback_param = priv;
cookie = dmaengine_submit(tx);
ret = dma_submit_error(cookie);
if (ret) {
dev_err(priv->ctlr->dev, "dma_submit_error %d\n", cookie);
goto unmap_dma;
}
dma_async_issue_pending(rx_chan);
if (!wait_for_completion_timeout(&priv->rx_dma_complete, msecs_to_jiffies(len + 1000))) {
dmaengine_terminate_sync(rx_chan);
dev_err(priv->ctlr->dev, "DMA wait_for_completion_timeout\n");
ret = -ETIMEDOUT;
}
unmap_dma:
dma_unmap_single(rx_chan->device->dev, dma_dst, len, DMA_FROM_DEVICE);
return ret;
}
static void am654_hbmc_read(struct hyperbus_device *hbdev, void *to,
unsigned long from, ssize_t len)
{
struct am654_hbmc_device_priv *priv = hbdev->priv;
if (len < SZ_1K || am654_hbmc_dma_read(priv, to, from, len))
memcpy_fromio(to, hbdev->map.virt + from, len);
}
static const struct hyperbus_ops am654_hbmc_ops = {
.calibrate = am654_hbmc_calibrate,
.copy_from = am654_hbmc_read,
};
static int am654_hbmc_request_mmap_dma(struct am654_hbmc_device_priv *priv)
{
struct dma_chan *rx_chan;
dma_cap_mask_t mask;
dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, mask);
rx_chan = dma_request_chan_by_mask(&mask);
if (IS_ERR(rx_chan)) {
if (PTR_ERR(rx_chan) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_dbg(priv->ctlr->dev, "No DMA channel available\n");
return 0;
}
priv->rx_chan = rx_chan;
init_completion(&priv->rx_dma_complete);
return 0;
}
static int am654_hbmc_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct am654_hbmc_device_priv *dev_priv;
struct device *dev = &pdev->dev;
struct am654_hbmc_priv *priv;
struct resource res;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
platform_set_drvdata(pdev, priv);
priv->hbdev.np = of_get_next_child(np, NULL);
ret = of_address_to_resource(priv->hbdev.np, 0, &res);
if (ret)
return ret;
if (of_property_read_bool(dev->of_node, "mux-controls")) {
struct mux_control *control = devm_mux_control_get(dev, NULL);
if (IS_ERR(control))
return PTR_ERR(control);
ret = mux_control_select(control, 1);
if (ret) {
dev_err(dev, "Failed to select HBMC mux\n");
return ret;
}
priv->mux_ctrl = control;
}
priv->hbdev.map.size = resource_size(&res);
priv->hbdev.map.virt = devm_ioremap_resource(dev, &res);
if (IS_ERR(priv->hbdev.map.virt))
return PTR_ERR(priv->hbdev.map.virt);
priv->ctlr.dev = dev;
priv->ctlr.ops = &am654_hbmc_ops;
priv->hbdev.ctlr = &priv->ctlr;
dev_priv = devm_kzalloc(dev, sizeof(*dev_priv), GFP_KERNEL);
if (!dev_priv) {
ret = -ENOMEM;
goto disable_mux;
}
priv->hbdev.priv = dev_priv;
dev_priv->device_base = res.start;
dev_priv->ctlr = &priv->ctlr;
ret = am654_hbmc_request_mmap_dma(dev_priv);
if (ret)
goto disable_mux;
ret = hyperbus_register_device(&priv->hbdev);
if (ret) {
dev_err(dev, "failed to register controller\n");
goto release_dma;
}
return 0;
release_dma:
if (dev_priv->rx_chan)
dma_release_channel(dev_priv->rx_chan);
disable_mux:
if (priv->mux_ctrl)
mux_control_deselect(priv->mux_ctrl);
return ret;
}
static int am654_hbmc_remove(struct platform_device *pdev)
{
struct am654_hbmc_priv *priv = platform_get_drvdata(pdev);
struct am654_hbmc_device_priv *dev_priv = priv->hbdev.priv;
hyperbus_unregister_device(&priv->hbdev);
if (priv->mux_ctrl)
mux_control_deselect(priv->mux_ctrl);
if (dev_priv->rx_chan)
dma_release_channel(dev_priv->rx_chan);
return 0;
}
static const struct of_device_id am654_hbmc_dt_ids[] = {
{
.compatible = "ti,am654-hbmc",
},
{ }
};
MODULE_DEVICE_TABLE(of, am654_hbmc_dt_ids);
static struct platform_driver am654_hbmc_platform_driver = {
.probe = am654_hbmc_probe,
.remove = am654_hbmc_remove,
.driver = {
.name = "hbmc-am654",
.of_match_table = am654_hbmc_dt_ids,
},
};
module_platform_driver(am654_hbmc_platform_driver);
MODULE_DESCRIPTION("HBMC driver for AM654 SoC");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:hbmc-am654");
MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>"