spi: pxa2xx: Remove redundant ->read() and ->write() in struct chip_data

Since the commit 196b0e2cf237 ("spi: pxa2xx: Remove if statement
that is always true in pump_transfers()") the ->read() and ->write()
methods in the struct driver_data are reconfigured for each transfer.
Hence no need to keep the intermediate state in the struct chip_data.

The same applies to n_bytes member of the same data structure.
Get rid of unneeded storage for good.

Signed-off-by: Andy Shevchenko <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

drivers/spi/spi-pxa2xx.c

···
 		dev_err(&spi->dev, "Flush failed\n");
 		return -EIO;
 	}
-	drv_data->n_bytes = chip->n_bytes;
 	drv_data->tx = (void *)transfer->tx_buf;
 	drv_data->tx_end = drv_data->tx + transfer->len;
 	drv_data->rx = transfer->rx_buf;
 	drv_data->rx_end = drv_data->rx + transfer->len;
-	drv_data->write = drv_data->tx ? chip->write : null_writer;
-	drv_data->read = drv_data->rx ? chip->read : null_reader;
 
 	/* Change speed and bit per word on a per transfer */
 	bits = transfer->bits_per_word;
···
 
 	if (bits <= 8) {
 		drv_data->n_bytes = 1;
-		drv_data->read = drv_data->read != null_reader ?
-					u8_reader : null_reader;
-		drv_data->write = drv_data->write != null_writer ?
-					u8_writer : null_writer;
+		drv_data->read = drv_data->rx ? u8_reader : null_reader;
+		drv_data->write = drv_data->tx ? u8_writer : null_writer;
 	} else if (bits <= 16) {
 		drv_data->n_bytes = 2;
-		drv_data->read = drv_data->read != null_reader ?
-					u16_reader : null_reader;
-		drv_data->write = drv_data->write != null_writer ?
-					u16_writer : null_writer;
+		drv_data->read = drv_data->rx ? u16_reader : null_reader;
+		drv_data->write = drv_data->tx ? u16_writer : null_writer;
 	} else if (bits <= 32) {
 		drv_data->n_bytes = 4;
-		drv_data->read = drv_data->read != null_reader ?
-					u32_reader : null_reader;
-		drv_data->write = drv_data->write != null_writer ?
-					u32_writer : null_writer;
+		drv_data->read = drv_data->rx ? u32_reader : null_reader;
+		drv_data->write = drv_data->tx ? u32_writer : null_writer;
 	}
 	/*
 	 * If bits per word is changed in DMA mode, then must check
···
 
 	if (spi->mode & SPI_LOOP)
 		chip->cr1 |= SSCR1_LBM;
-
-	if (spi->bits_per_word <= 8) {
-		chip->n_bytes = 1;
-		chip->read = u8_reader;
-		chip->write = u8_writer;
-	} else if (spi->bits_per_word <= 16) {
-		chip->n_bytes = 2;
-		chip->read = u16_reader;
-		chip->write = u16_writer;
-	} else if (spi->bits_per_word <= 32) {
-		chip->n_bytes = 4;
-		chip->read = u32_reader;
-		chip->write = u32_writer;
-	}
 
 	spi_set_ctldata(spi, chip);
 

drivers/spi/spi-pxa2xx.h

···
 	u32 cr1;
 	u32 dds_rate;
 	u32 timeout;
-	u8 n_bytes;
 	u8 enable_dma;
 	u32 dma_burst_size;
 	u32 dma_threshold;
 	u32 threshold;
 	u16 lpss_rx_threshold;
 	u16 lpss_tx_threshold;
-
-	int (*write)(struct driver_data *drv_data);
-	int (*read)(struct driver_data *drv_data);
 
 	void (*cs_control)(u32 command);
 };