spicc: support irregular bit-width

PD#162464: spicc: support irregular bit-width

some device work at a irregular bit-width for example,
11 bit-width and tx data is {0xa1, 0x62},
the LSB bit order is: 10100001 011 (0xa1 + 3 bits of 0x62)
the MSB bit order is: 01100010 101 (0x62 + 3 bits of 0xa1)
note: all case more than 16 bits will run at 4-byte-per-word though one
byte discarded.

to print the difference between tx and rx if mode[16]=1

Change-Id: Ibdd438c3fe764986c71b77ec2d4fa0db489dd439
Signed-off-by: Sunny Luo <sunny.luo@amlogic.com>

diff --git a/drivers/amlogic/spicc/spicc.c b/drivers/amlogic/spicc/spicc.c
index e49d331..e4b6150 100644 (file)
--- a/drivers/amlogic/spicc/spicc.c
+++ b/drivers/amlogic/spicc/spicc.c
@@ -77,6 +77,7 @@ struct spicc {
        struct pinctrl_state *pullup;
        struct pinctrl_state *pulldown;
        int bytes_per_word;
+       int bit_offset;
        int mode;
        int speed;
        unsigned int dma_tx_threshold;
@@ -285,7 +286,15 @@ static inline void spicc_set_flag(
 static inline void spicc_set_bit_width(struct spicc *spicc, u8 bw)
 {
        setb(spicc->regs, CON_BITS_PER_WORD, bw-1);
-       spicc->bytes_per_word = ((bw - 1) >> 3) + 1;
+       if (bw <= 8)
+               spicc->bytes_per_word = 1;
+       else if (bw <= 16)
+               spicc->bytes_per_word = 2;
+       else if (bw <= 32)
+               spicc->bytes_per_word = 4;
+       else
+               spicc->bytes_per_word = 8;
+       spicc->bit_offset = (spicc->bytes_per_word << 3) - bw;
 }
 
 static void spicc_set_mode(struct spicc *spicc, u8 mode)
@@ -404,7 +413,7 @@ static inline u32 spicc_pull_data(struct spicc *spicc)
                        dat |= *spicc->txp << (i << 3);
                        spicc->txp++;
                }
-
+       dat >>= spicc->bit_offset;
        return dat;
 }
 
@@ -413,6 +422,7 @@ static inline void spicc_push_data(struct spicc *spicc, u32 dat)
        int bytes = spicc->bytes_per_word;
        int i;
 
+       dat <<= spicc->bit_offset;
        if (spicc->mode & SPI_LSB_FIRST)
                for (i = 0; i < bytes; i++)
                        *spicc->rxp++ = dat >> ((bytes - i - 1) << 3);
@@ -554,14 +564,11 @@ static int spicc_dma_xfer(struct spicc *spicc, struct spi_transfer *t)
        spicc_reset_fifo(spicc);
        setb(mem_base, CON_XCH, 0);
        setb(mem_base, WAIT_CYCLES, spicc->speed >> 25);
-       spicc_set_bit_width(spicc, 64);
        if (t->tx_dma != INVALID_DMA_ADDRESS)
                writel(t->tx_dma, mem_base + SPICC_REG_DRADDR);
        if (t->rx_dma != INVALID_DMA_ADDRESS)
                writel(t->rx_dma, mem_base + SPICC_REG_DWADDR);
        setb(mem_base, DMA_EN, 1);
-       spicc->remain = ((t->len - 1) >> 3) + 1;
-       spicc->burst_len = 0;
        spicc_log(spicc, &spicc->remain, 1, DMA_BEGIN);
        if (spicc->irq) {
                setb(mem_base, INT_XFER_COM_EN, 1);
@@ -600,7 +607,6 @@ static int spicc_hw_xfer(struct spicc *spicc, u8 *txp, u8 *rxp, int len)
        spicc_reset_fifo(spicc);
        setb(mem_base, CON_XCH, 0);
        setb(mem_base, WAIT_CYCLES, 0);
-       spicc->remain = len / spicc->bytes_per_word;
        spicc->txp = txp;
        spicc->rxp = rxp;
        spicc_log(spicc, &spicc->remain, 1, PIO_BEGIN);
@@ -716,7 +722,7 @@ static int spicc_setup(struct spi_device *spi)
        spicc = spi_master_get_devdata(spi->master);
        if (spi->cs_gpio >= 0)
                gpio_request(spi->cs_gpio, "spicc");
-       dev_info(&spi->dev, "chip_select=%d cs_gpio=%d mode=%d speed=%d\n",
+       dev_info(&spi->dev, "cs=%d cs_gpio=%d mode=0x%x speed=%d\n",
                        spi->chip_select, spi->cs_gpio,
                        spi->mode, spi->max_speed_hz);
        spicc_chip_select(spi, 0);
@@ -759,6 +765,7 @@ static void spicc_handle_one_msg(struct spicc *spicc, struct spi_message *m)
                if (t->delay_usecs >> 10)
                        udelay(t->delay_usecs >> 10);
 
+               spicc->remain = t->len / spicc->bytes_per_word;
                spicc_set_flag(spicc, FLAG_DMA_EN, 0);
                if (t->bits_per_word == 64) {
                        spicc_set_flag(spicc, FLAG_DMA_EN, 1);
@@ -880,7 +887,7 @@ static ssize_t store_test(
        u8 *tx_buf, *rx_buf;
        unsigned long value;
        char *kstr, *str_temp, *token;
-       int i, ret, bytes_per_word;
+       int i, ret;
        struct spi_transfer t;
        struct spi_message m;
 
@@ -889,8 +896,7 @@ static ssize_t store_test(
                dev_err(dev, "error format\n");
                return count;
        }
-       bytes_per_word = ((bits_per_word - 1) >> 3) + 1;
-       if (!speed || !num || !bits_per_word || num % bytes_per_word) {
+       if (!speed || !num || !bits_per_word) {
                dev_err(dev, "error parameter\n");
                return count;
        }
@@ -928,7 +934,7 @@ static ssize_t store_test(
                m.spi->chip_select = cs_gpio - 1000;
        }
        m.spi->max_speed_hz = speed;
-       m.spi->mode = mode;
+       m.spi->mode = mode & 0xffff;
        m.spi->bits_per_word = bits_per_word;
        spicc_setup(m.spi);
        memset(&t, 0, sizeof(t));
@@ -944,7 +950,7 @@ static ssize_t store_test(
                goto test_end;
        }
 
-       if (mode & SPI_LOOP) {
+       if (mode & (SPI_LOOP | (1<<16))) {
                ret = 0;
                for (i = 0; i < num; i++) {
                        if (tx_buf[i] != rx_buf[i]) {