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spi: microchip-core: add support for word sizes of 1 to 32 bits

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The current implementation only supports a word size of 8 bits,
which limits the devices it can be used with. Add support for any
word size between 1 and 32 bits, as supported by the hardware.

Signed-off-by: Steve Wilkins <steve.wilkins@raymarine.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20240715-cogwheel-uniquely-0d4ef518b809@wendy
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Steve Wilkins 2024-07-15 12:13:57 +01:00 committed by Mark Brown
parent 9cf71eb0fa
commit 87232ea8a5
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
1 changed files with 31 additions and 22 deletions
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53
drivers/spi/spi-microchip-core.c
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@ -111,7 +111,7 @@ struct mchp_corespi {
int irq;
int tx_len;
int rx_len;
int pending;
int n_bytes;
};
static inline u32 mchp_corespi_read(struct mchp_corespi *spi, unsigned int reg)
@ -135,20 +135,23 @@ static inline void mchp_corespi_disable(struct mchp_corespi *spi)
static inline void mchp_corespi_read_fifo(struct mchp_corespi *spi)
{
u8 data;
int fifo_max, i = 0;
while (spi->rx_len >= spi->n_bytes && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_RXFIFO_EMPTY)) {
u32 data = mchp_corespi_read(spi, REG_RX_DATA);
fifo_max = min(spi->rx_len, FIFO_DEPTH);
spi->rx_len -= spi->n_bytes;
while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_RXFIFO_EMPTY)) {
data = mchp_corespi_read(spi, REG_RX_DATA);
if (!spi->rx_buf)
continue;
if (spi->rx_buf)
*spi->rx_buf++ = data;
i++;
if (spi->n_bytes == 4)
*((u32 *)spi->rx_buf) = data;
else if (spi->n_bytes == 2)
*((u16 *)spi->rx_buf) = data;
else
*spi->rx_buf = data;
spi->rx_buf += spi->n_bytes;
}
spi->rx_len -= i;
spi->pending -= i;
}
static void mchp_corespi_enable_ints(struct mchp_corespi *spi)
@ -210,20 +213,28 @@ static inline void mchp_corespi_set_xfer_size(struct mchp_corespi *spi, int len)
static inline void mchp_corespi_write_fifo(struct mchp_corespi *spi)
{
u8 byte;
int fifo_max, i = 0;
fifo_max = min(spi->tx_len, FIFO_DEPTH);
fifo_max = DIV_ROUND_UP(min(spi->tx_len, FIFO_DEPTH), spi->n_bytes);
mchp_corespi_set_xfer_size(spi, fifo_max);
while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_TXFIFO_FULL)) {
byte = spi->tx_buf ? *spi->tx_buf++ : 0xaa;
mchp_corespi_write(spi, REG_TX_DATA, byte);
u32 word;
if (spi->n_bytes == 4)
word = spi->tx_buf ? *((u32 *)spi->tx_buf) : 0xaa;
else if (spi->n_bytes == 2)
word = spi->tx_buf ? *((u16 *)spi->tx_buf) : 0xaa;
else
word = spi->tx_buf ? *spi->tx_buf : 0xaa;
mchp_corespi_write(spi, REG_TX_DATA, word);
if (spi->tx_buf)
spi->tx_buf += spi->n_bytes;
i++;
}
spi->tx_len -= i;
spi->pending += i;
spi->tx_len -= i * spi->n_bytes;
}
static inline void mchp_corespi_set_framesize(struct mchp_corespi *spi, int bt)
@ -493,10 +504,9 @@ static int mchp_corespi_transfer_one(struct spi_controller *host,
spi->rx_buf = xfer->rx_buf;
spi->tx_len = xfer->len;
spi->rx_len = xfer->len;
spi->pending = 0;
spi->n_bytes = roundup_pow_of_two(DIV_ROUND_UP(xfer->bits_per_word, BITS_PER_BYTE));
mchp_corespi_set_xfer_size(spi, (spi->tx_len > FIFO_DEPTH)
? FIFO_DEPTH : spi->tx_len);
mchp_corespi_set_framesize(spi, xfer->bits_per_word);
mchp_corespi_write(spi, REG_COMMAND, COMMAND_RXFIFORST | COMMAND_TXFIFORST);
@ -514,7 +524,6 @@ static int mchp_corespi_prepare_message(struct spi_controller *host,
struct spi_device *spi_dev = msg->spi;
struct mchp_corespi *spi = spi_controller_get_devdata(host);
mchp_corespi_set_framesize(spi, DEFAULT_FRAMESIZE);
mchp_corespi_set_mode(spi, spi_dev->mode);
return 0;
@ -542,7 +551,7 @@ static int mchp_corespi_probe(struct platform_device *pdev)
host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
host->use_gpio_descriptors = true;
host->setup = mchp_corespi_setup;
host->bits_per_word_mask = SPI_BPW_MASK(8);
host->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
host->transfer_one = mchp_corespi_transfer_one;
host->prepare_message = mchp_corespi_prepare_message;
host->set_cs = mchp_corespi_set_cs;