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spi: spi-ep93xx: pass the spi_master pointer around
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Change the parameters for some of the functions so that the spi_master
pointer is passed around instead of the private data ep93xx_spi pointer.

This allows removing the 'pdev' member of the private data and will
help with some later cleanup.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Mark Brown <broonie@kernel.org>
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H Hartley Sweeten authored and Mark Brown committed Aug 9, 2017
1 parent ac8d06d commit 4873883
Showing 1 changed file with 49 additions and 41 deletions.
90 changes: 49 additions & 41 deletions drivers/spi/spi-ep93xx.c
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Original file line number Diff line number Diff line change
Expand Up @@ -70,7 +70,6 @@

/**
* struct ep93xx_spi - EP93xx SPI controller structure
* @pdev: pointer to platform device
* @clk: clock for the controller
* @mmio: pointer to ioremap()'d registers
* @sspdr_phys: physical address of the SSPDR register
Expand All @@ -90,7 +89,6 @@
* the client
*/
struct ep93xx_spi {
const struct platform_device *pdev;
struct clk *clk;
void __iomem *mmio;
unsigned long sspdr_phys;
Expand All @@ -113,15 +111,15 @@ struct ep93xx_spi {

/**
* ep93xx_spi_calc_divisors() - calculates SPI clock divisors
* @espi: ep93xx SPI controller struct
* @master: SPI master
* @rate: desired SPI output clock rate
* @div_cpsr: pointer to return the cpsr (pre-scaler) divider
* @div_scr: pointer to return the scr divider
*/
static int ep93xx_spi_calc_divisors(const struct ep93xx_spi *espi,
static int ep93xx_spi_calc_divisors(struct spi_master *master,
u32 rate, u8 *div_cpsr, u8 *div_scr)
{
struct spi_master *master = platform_get_drvdata(espi->pdev);
struct ep93xx_spi *espi = spi_master_get_devdata(master);
unsigned long spi_clk_rate = clk_get_rate(espi->clk);
int cpsr, scr;

Expand Down Expand Up @@ -162,17 +160,18 @@ static void ep93xx_spi_cs_control(struct spi_device *spi, bool enable)
gpio_set_value(spi->cs_gpio, !enable);
}

static int ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
static int ep93xx_spi_chip_setup(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
u8 dss = bits_per_word_to_dss(xfer->bits_per_word);
u8 div_cpsr = 0;
u8 div_scr = 0;
u16 cr0;
int err;

err = ep93xx_spi_calc_divisors(espi, xfer->speed_hz,
err = ep93xx_spi_calc_divisors(master, xfer->speed_hz,
&div_cpsr, &div_scr);
if (err)
return err;
Expand All @@ -181,9 +180,9 @@ static int ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
cr0 |= (spi->mode & (SPI_CPHA | SPI_CPOL)) << SSPCR0_MODE_SHIFT;
cr0 |= dss;

dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
dev_dbg(&master->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
spi->mode, div_cpsr, div_scr, dss);
dev_dbg(&espi->pdev->dev, "setup: cr0 %#x\n", cr0);
dev_dbg(&master->dev, "setup: cr0 %#x\n", cr0);

writel(div_cpsr, espi->mmio + SSPCPSR);
writel(cr0, espi->mmio + SSPCR0);
Expand Down Expand Up @@ -234,8 +233,9 @@ static void ep93xx_do_read(struct ep93xx_spi *espi, struct spi_transfer *t)
* When this function is finished, RX FIFO should be empty and TX FIFO should be
* full.
*/
static int ep93xx_spi_read_write(struct ep93xx_spi *espi)
static int ep93xx_spi_read_write(struct spi_master *master)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
struct spi_message *msg = espi->current_msg;
struct spi_transfer *t = msg->state;

Expand All @@ -257,13 +257,15 @@ static int ep93xx_spi_read_write(struct ep93xx_spi *espi)
return -EINPROGRESS;
}

static void ep93xx_spi_pio_transfer(struct ep93xx_spi *espi)
static void ep93xx_spi_pio_transfer(struct spi_master *master)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);

/*
* Now everything is set up for the current transfer. We prime the TX
* FIFO, enable interrupts, and wait for the transfer to complete.
*/
if (ep93xx_spi_read_write(espi)) {
if (ep93xx_spi_read_write(master)) {
u32 val;

val = readl(espi->mmio + SSPCR1);
Expand All @@ -276,16 +278,18 @@ static void ep93xx_spi_pio_transfer(struct ep93xx_spi *espi)

/**
* ep93xx_spi_dma_prepare() - prepares a DMA transfer
* @espi: ep93xx SPI controller struct
* @master: SPI master
* @dir: DMA transfer direction
*
* Function configures the DMA, maps the buffer and prepares the DMA
* descriptor. Returns a valid DMA descriptor in case of success and ERR_PTR
* in case of failure.
*/
static struct dma_async_tx_descriptor *
ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir)
ep93xx_spi_dma_prepare(struct spi_master *master,
enum dma_transfer_direction dir)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
struct spi_transfer *t = espi->current_msg->state;
struct dma_async_tx_descriptor *txd;
enum dma_slave_buswidth buswidth;
Expand Down Expand Up @@ -361,7 +365,7 @@ ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir)
}

if (WARN_ON(len)) {
dev_warn(&espi->pdev->dev, "len = %zu expected 0!\n", len);
dev_warn(&master->dev, "len = %zu expected 0!\n", len);
return ERR_PTR(-EINVAL);
}

Expand All @@ -379,15 +383,16 @@ ep93xx_spi_dma_prepare(struct ep93xx_spi *espi, enum dma_transfer_direction dir)

/**
* ep93xx_spi_dma_finish() - finishes with a DMA transfer
* @espi: ep93xx SPI controller struct
* @master: SPI master
* @dir: DMA transfer direction
*
* Function finishes with the DMA transfer. After this, the DMA buffer is
* unmapped.
*/
static void ep93xx_spi_dma_finish(struct ep93xx_spi *espi,
static void ep93xx_spi_dma_finish(struct spi_master *master,
enum dma_transfer_direction dir)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
struct dma_chan *chan;
struct sg_table *sgt;

Expand All @@ -407,22 +412,23 @@ static void ep93xx_spi_dma_callback(void *callback_param)
complete(callback_param);
}

static void ep93xx_spi_dma_transfer(struct ep93xx_spi *espi)
static void ep93xx_spi_dma_transfer(struct spi_master *master)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
struct spi_message *msg = espi->current_msg;
struct dma_async_tx_descriptor *rxd, *txd;

rxd = ep93xx_spi_dma_prepare(espi, DMA_DEV_TO_MEM);
rxd = ep93xx_spi_dma_prepare(master, DMA_DEV_TO_MEM);
if (IS_ERR(rxd)) {
dev_err(&espi->pdev->dev, "DMA RX failed: %ld\n", PTR_ERR(rxd));
dev_err(&master->dev, "DMA RX failed: %ld\n", PTR_ERR(rxd));
msg->status = PTR_ERR(rxd);
return;
}

txd = ep93xx_spi_dma_prepare(espi, DMA_MEM_TO_DEV);
txd = ep93xx_spi_dma_prepare(master, DMA_MEM_TO_DEV);
if (IS_ERR(txd)) {
ep93xx_spi_dma_finish(espi, DMA_DEV_TO_MEM);
dev_err(&espi->pdev->dev, "DMA TX failed: %ld\n", PTR_ERR(txd));
ep93xx_spi_dma_finish(master, DMA_DEV_TO_MEM);
dev_err(&master->dev, "DMA TX failed: %ld\n", PTR_ERR(txd));
msg->status = PTR_ERR(txd);
return;
}
Expand All @@ -440,31 +446,32 @@ static void ep93xx_spi_dma_transfer(struct ep93xx_spi *espi)

wait_for_completion(&espi->wait);

ep93xx_spi_dma_finish(espi, DMA_MEM_TO_DEV);
ep93xx_spi_dma_finish(espi, DMA_DEV_TO_MEM);
ep93xx_spi_dma_finish(master, DMA_MEM_TO_DEV);
ep93xx_spi_dma_finish(master, DMA_DEV_TO_MEM);
}

/**
* ep93xx_spi_process_transfer() - processes one SPI transfer
* @espi: ep93xx SPI controller struct
* @master: SPI master
* @msg: current message
* @t: transfer to process
*
* This function processes one SPI transfer given in @t. Function waits until
* transfer is complete (may sleep) and updates @msg->status based on whether
* transfer was successfully processed or not.
*/
static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
static void ep93xx_spi_process_transfer(struct spi_master *master,
struct spi_message *msg,
struct spi_transfer *t)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
int err;

msg->state = t;

err = ep93xx_spi_chip_setup(espi, msg->spi, t);
err = ep93xx_spi_chip_setup(master, msg->spi, t);
if (err) {
dev_err(&espi->pdev->dev,
dev_err(&master->dev,
"failed to setup chip for transfer\n");
msg->status = err;
return;
Expand All @@ -479,9 +486,9 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
* So in these cases we will be using PIO and don't bother for DMA.
*/
if (espi->dma_rx && t->len > SPI_FIFO_SIZE)
ep93xx_spi_dma_transfer(espi);
ep93xx_spi_dma_transfer(master);
else
ep93xx_spi_pio_transfer(espi);
ep93xx_spi_pio_transfer(master);

/*
* In case of error during transmit, we bail out from processing
Expand Down Expand Up @@ -516,7 +523,7 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,

/*
* ep93xx_spi_process_message() - process one SPI message
* @espi: ep93xx SPI controller struct
* @master: SPI master
* @msg: message to process
*
* This function processes a single SPI message. We go through all transfers in
Expand All @@ -526,9 +533,10 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
* @msg->status contains %0 in case of success or negative error code in case of
* failure.
*/
static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
static void ep93xx_spi_process_message(struct spi_master *master,
struct spi_message *msg)
{
struct ep93xx_spi *espi = spi_master_get_devdata(master);
unsigned long timeout;
struct spi_transfer *t;

Expand All @@ -538,7 +546,7 @@ static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
timeout = jiffies + msecs_to_jiffies(SPI_TIMEOUT);
while (readl(espi->mmio + SSPSR) & SSPSR_RNE) {
if (time_after(jiffies, timeout)) {
dev_warn(&espi->pdev->dev,
dev_warn(&master->dev,
"timeout while flushing RX FIFO\n");
msg->status = -ETIMEDOUT;
return;
Expand All @@ -558,7 +566,7 @@ static void ep93xx_spi_process_message(struct ep93xx_spi *espi,
ep93xx_spi_cs_control(msg->spi, true);

list_for_each_entry(t, &msg->transfers, transfer_list) {
ep93xx_spi_process_transfer(espi, msg, t);
ep93xx_spi_process_transfer(master, msg, t);
if (msg->status)
break;
}
Expand All @@ -580,7 +588,7 @@ static int ep93xx_spi_transfer_one_message(struct spi_master *master,
msg->actual_length = 0;

espi->current_msg = msg;
ep93xx_spi_process_message(espi, msg);
ep93xx_spi_process_message(master, msg);
espi->current_msg = NULL;

spi_finalize_current_message(master);
Expand All @@ -590,7 +598,8 @@ static int ep93xx_spi_transfer_one_message(struct spi_master *master,

static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id)
{
struct ep93xx_spi *espi = dev_id;
struct spi_master *master = dev_id;
struct ep93xx_spi *espi = spi_master_get_devdata(master);
u32 val;

/*
Expand All @@ -600,15 +609,15 @@ static irqreturn_t ep93xx_spi_interrupt(int irq, void *dev_id)
if (readl(espi->mmio + SSPIIR) & SSPIIR_RORIS) {
/* clear the overrun interrupt */
writel(0, espi->mmio + SSPICR);
dev_warn(&espi->pdev->dev,
dev_warn(&master->dev,
"receive overrun, aborting the message\n");
espi->current_msg->status = -EIO;
} else {
/*
* Interrupt is either RX (RIS) or TX (TIS). For both cases we
* simply execute next data transfer.
*/
if (ep93xx_spi_read_write(espi)) {
if (ep93xx_spi_read_write(master)) {
/*
* In normal case, there still is some processing left
* for current transfer. Let's wait for the next
Expand Down Expand Up @@ -815,7 +824,6 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
*/
master->max_speed_hz = clk_get_rate(espi->clk) / 2;
master->min_speed_hz = clk_get_rate(espi->clk) / (254 * 256);
espi->pdev = pdev;

espi->sspdr_phys = res->start + SSPDR;

Expand All @@ -826,7 +834,7 @@ static int ep93xx_spi_probe(struct platform_device *pdev)
}

error = devm_request_irq(&pdev->dev, irq, ep93xx_spi_interrupt,
0, "ep93xx-spi", espi);
0, "ep93xx-spi", master);
if (error) {
dev_err(&pdev->dev, "failed to request irq\n");
goto fail_release_master;
Expand Down

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