[PATCH 3/3] net: irda: pxaficp_ir: dmaengine conversion

From: Robert Jarzmik
Date: Thu Sep 03 2015 - 02:26:23 EST


Convert pxaficp_ir to dmaengine. As pxa architecture is shifting from
raw DMA registers access to pxa_dma dmaengine driver, convert this
driver to dmaengine.

Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxx>
---
drivers/net/irda/pxaficp_ir.c | 145 +++++++++++++++++++++++++++++-------------
1 file changed, 102 insertions(+), 43 deletions(-)

diff --git a/drivers/net/irda/pxaficp_ir.c b/drivers/net/irda/pxaficp_ir.c
index 519f6b0568a8..42318fb2c95a 100644
--- a/drivers/net/irda/pxaficp_ir.c
+++ b/drivers/net/irda/pxaficp_ir.c
@@ -19,6 +19,9 @@
#include <linux/etherdevice.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma/pxa-dma.h>
#include <linux/gpio.h>
#include <linux/slab.h>

@@ -146,8 +149,12 @@ struct pxa_irda {
dma_addr_t dma_rx_buff_phy;
dma_addr_t dma_tx_buff_phy;
unsigned int dma_tx_buff_len;
- int txdma;
- int rxdma;
+ struct dma_chan *txdma;
+ struct dma_chan *rxdma;
+ dma_cookie_t rx_cookie;
+ dma_cookie_t tx_cookie;
+ int drcmr_rx;
+ int drcmr_tx;

int uart_irq;
int icp_irq;
@@ -165,6 +172,8 @@ struct pxa_irda {
struct clk *cur_clk;
};

+static int pxa_irda_set_speed(struct pxa_irda *si, int speed);
+
static inline void pxa_irda_disable_clk(struct pxa_irda *si)
{
if (si->cur_clk)
@@ -188,22 +197,41 @@ static inline void pxa_irda_enable_sirclk(struct pxa_irda *si)
#define IS_FIR(si) ((si)->speed >= 4000000)
#define IRDA_FRAME_SIZE_LIMIT 2047

+static void pxa_irda_fir_dma_rx_irq(void *data);
+static void pxa_irda_fir_dma_tx_irq(void *data);
+
inline static void pxa_irda_fir_dma_rx_start(struct pxa_irda *si)
{
- DCSR(si->rxdma) = DCSR_NODESC;
- DSADR(si->rxdma) = (unsigned long)si->irda_base + ICDR;
- DTADR(si->rxdma) = si->dma_rx_buff_phy;
- DCMD(si->rxdma) = DCMD_INCTRGADDR | DCMD_FLOWSRC | DCMD_WIDTH1 | DCMD_BURST32 | IRDA_FRAME_SIZE_LIMIT;
- DCSR(si->rxdma) |= DCSR_RUN;
+ struct dma_async_tx_descriptor *tx;
+
+ tx = dmaengine_prep_slave_single(si->rxdma, si->dma_rx_buff_phy,
+ IRDA_FRAME_SIZE_LIMIT, DMA_FROM_DEVICE,
+ DMA_PREP_INTERRUPT);
+ if (!tx) {
+ dev_err(si->dev, "prep_slave_sg() failed\n");
+ return;
+ }
+ tx->callback = pxa_irda_fir_dma_rx_irq;
+ tx->callback_param = si;
+ si->rx_cookie = dmaengine_submit(tx);
+ dma_async_issue_pending(si->rxdma);
}

inline static void pxa_irda_fir_dma_tx_start(struct pxa_irda *si)
{
- DCSR(si->txdma) = DCSR_NODESC;
- DSADR(si->txdma) = si->dma_tx_buff_phy;
- DTADR(si->txdma) = (unsigned long)si->irda_base + ICDR;
- DCMD(si->txdma) = DCMD_INCSRCADDR | DCMD_FLOWTRG | DCMD_ENDIRQEN | DCMD_WIDTH1 | DCMD_BURST32 | si->dma_tx_buff_len;
- DCSR(si->txdma) |= DCSR_RUN;
+ struct dma_async_tx_descriptor *tx;
+
+ tx = dmaengine_prep_slave_single(si->txdma, si->dma_tx_buff_phy,
+ si->dma_tx_buff_len, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT);
+ if (!tx) {
+ dev_err(si->dev, "prep_slave_sg() failed\n");
+ return;
+ }
+ tx->callback = pxa_irda_fir_dma_tx_irq;
+ tx->callback_param = si;
+ si->tx_cookie = dmaengine_submit(tx);
+ dma_async_issue_pending(si->rxdma);
}

/*
@@ -242,7 +270,7 @@ static int pxa_irda_set_speed(struct pxa_irda *si, int speed)

if (IS_FIR(si)) {
/* stop RX DMA */
- DCSR(si->rxdma) &= ~DCSR_RUN;
+ dmaengine_terminate_all(si->rxdma);
/* disable FICP */
ficp_writel(si, 0, ICCR0);
pxa_irda_disable_clk(si);
@@ -388,30 +416,27 @@ static irqreturn_t pxa_irda_sir_irq(int irq, void *dev_id)
}

/* FIR Receive DMA interrupt handler */
-static void pxa_irda_fir_dma_rx_irq(int channel, void *data)
+static void pxa_irda_fir_dma_rx_irq(void *data)
{
- int dcsr = DCSR(channel);
-
- DCSR(channel) = dcsr & ~DCSR_RUN;
+ struct net_device *dev = data;
+ struct pxa_irda *si = netdev_priv(dev);

- printk(KERN_DEBUG "pxa_ir: fir rx dma bus error %#x\n", dcsr);
+ dmaengine_terminate_all(si->rxdma);
+ netdev_dbg(dev, "pxa_ir: fir rx dma bus error\n");
}

/* FIR Transmit DMA interrupt handler */
-static void pxa_irda_fir_dma_tx_irq(int channel, void *data)
+static void pxa_irda_fir_dma_tx_irq(void *data)
{
struct net_device *dev = data;
struct pxa_irda *si = netdev_priv(dev);
- int dcsr;
-
- dcsr = DCSR(channel);
- DCSR(channel) = dcsr & ~DCSR_RUN;

- if (dcsr & DCSR_ENDINTR) {
+ dmaengine_terminate_all(si->txdma);
+ if (dmaengine_tx_status(si->txdma, si->tx_cookie, NULL) == DMA_ERROR) {
+ dev->stats.tx_errors++;
+ } else {
dev->stats.tx_packets++;
dev->stats.tx_bytes += si->dma_tx_buff_len;
- } else {
- dev->stats.tx_errors++;
}

while (ficp_readl(si, ICSR1) & ICSR1_TBY)
@@ -446,9 +471,12 @@ static void pxa_irda_fir_dma_tx_irq(int channel, void *data)
static void pxa_irda_fir_irq_eif(struct pxa_irda *si, struct net_device *dev, int icsr0)
{
unsigned int len, stat, data;
+ struct dma_tx_state state;

/* Get the current data position. */
- len = DTADR(si->rxdma) - si->dma_rx_buff_phy;
+
+ dmaengine_tx_status(si->rxdma, si->rx_cookie, &state);
+ len = IRDA_FRAME_SIZE_LIMIT - state.residue;

do {
/* Read Status, and then Data. */
@@ -515,7 +543,7 @@ static irqreturn_t pxa_irda_fir_irq(int irq, void *dev_id)
int icsr0, i = 64;

/* stop RX DMA */
- DCSR(si->rxdma) &= ~DCSR_RUN;
+ dmaengine_terminate_all(si->rxdma);
si->last_clk = sched_clock();
icsr0 = ficp_readl(si, ICSR0);

@@ -597,7 +625,7 @@ static int pxa_irda_hard_xmit(struct sk_buff *skb, struct net_device *dev)
cpu_relax();

/* stop RX DMA, disable FICP */
- DCSR(si->rxdma) &= ~DCSR_RUN;
+ dmaengine_terminate_all(si->rxdma);
ficp_writel(si, 0, ICCR0);

pxa_irda_fir_dma_tx_start(si);
@@ -670,10 +698,6 @@ static void pxa_irda_startup(struct pxa_irda *si)
/* configure FICP ICCR2 */
ficp_writel(si, ICCR2_TXP | ICCR2_TRIG_32, ICCR2);

- /* configure DMAC */
- DRCMR(17) = si->rxdma | DRCMR_MAPVLD;
- DRCMR(18) = si->txdma | DRCMR_MAPVLD;
-
/* force SIR reinitialization */
si->speed = 4000000;
pxa_irda_set_speed(si, 9600);
@@ -693,8 +717,8 @@ static void pxa_irda_shutdown(struct pxa_irda *si)
stuart_writel(si, 0, STISR);

/* disable DMA */
- DCSR(si->txdma) &= ~DCSR_RUN;
- DCSR(si->rxdma) &= ~DCSR_RUN;
+ dmaengine_terminate_all(si->rxdma);
+ dmaengine_terminate_all(si->txdma);
/* disable FICP */
ficp_writel(si, 0, ICCR0);

@@ -715,6 +739,9 @@ static void pxa_irda_shutdown(struct pxa_irda *si)
static int pxa_irda_start(struct net_device *dev)
{
struct pxa_irda *si = netdev_priv(dev);
+ dma_cap_mask_t mask;
+ struct dma_slave_config config;
+ struct pxad_param param;
int err;

si->speed = 9600;
@@ -734,14 +761,37 @@ static int pxa_irda_start(struct net_device *dev)
disable_irq(si->icp_irq);

err = -EBUSY;
- si->rxdma = pxa_request_dma("FICP_RX",DMA_PRIO_LOW, pxa_irda_fir_dma_rx_irq, dev);
- if (si->rxdma < 0)
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ param.prio = PXAD_PRIO_LOWEST;
+
+ memset(&config, 0, sizeof(config));
+ config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ config.src_addr = (dma_addr_t)si->irda_base + ICDR;
+ config.dst_addr = (dma_addr_t)si->irda_base + ICDR;
+ config.src_maxburst = 32;
+ config.dst_maxburst = 32;
+
+ param.drcmr = si->drcmr_rx;
+ si->rxdma = dma_request_slave_channel_compat(mask, pxad_filter_fn,
+ &param, &dev->dev, "rx");
+ if (!si->rxdma)
goto err_rx_dma;

- si->txdma = pxa_request_dma("FICP_TX",DMA_PRIO_LOW, pxa_irda_fir_dma_tx_irq, dev);
- if (si->txdma < 0)
+ param.drcmr = si->drcmr_tx;
+ si->txdma = dma_request_slave_channel_compat(mask, pxad_filter_fn,
+ &param, &dev->dev, "tx");
+ if (!si->txdma)
goto err_tx_dma;

+ err = dmaengine_slave_config(si->rxdma, &config);
+ if (err)
+ goto err_dma_rx_buff;
+ err = dmaengine_slave_config(si->txdma, &config);
+ if (err)
+ goto err_dma_rx_buff;
+
err = -ENOMEM;
si->dma_rx_buff = dma_alloc_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT,
&si->dma_rx_buff_phy, GFP_KERNEL);
@@ -781,9 +831,9 @@ err_irlap:
err_dma_tx_buff:
dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_rx_buff, si->dma_rx_buff_phy);
err_dma_rx_buff:
- pxa_free_dma(si->txdma);
+ dma_release_channel(si->txdma);
err_tx_dma:
- pxa_free_dma(si->rxdma);
+ dma_release_channel(si->rxdma);
err_rx_dma:
free_irq(si->icp_irq, dev);
err_irq2:
@@ -810,8 +860,10 @@ static int pxa_irda_stop(struct net_device *dev)
free_irq(si->uart_irq, dev);
free_irq(si->icp_irq, dev);

- pxa_free_dma(si->rxdma);
- pxa_free_dma(si->txdma);
+ dmaengine_terminate_all(si->rxdma);
+ dmaengine_terminate_all(si->txdma);
+ dma_release_channel(si->rxdma);
+ dma_release_channel(si->txdma);

if (si->dma_rx_buff)
dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_tx_buff, si->dma_tx_buff_phy);
@@ -920,6 +972,13 @@ static int pxa_irda_probe(struct platform_device *pdev)
goto err_mem_4;
}

+ res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+ if (res)
+ si->drcmr_rx = res->start;
+ res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+ if (res)
+ si->drcmr_tx = res->start;
+
/*
* Initialise the SIR buffers
*/
--
2.1.4

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