Unverified Commit fd806575 authored by Chuanhong Guo's avatar Chuanhong Guo Committed by Mark Brown
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spi: spi-mtk-nor: add helper for checking prg mode ops 



op checking/resizing logic for the newly added mtk_nor_spi_mem_prg is
more complicated. Add two helper functions for them:
mtk_nor_match_prg: check whether an op is supported by prg mode.
mtk_nor_adj_prg_size: adjust data size for mtk_nor_spi_mem_prg.

mtk_nor_match_prg isn't called yet because supports_op is currently
broken. It'll be used in the next fix commit.

Signed-off-by: default avatarChuanhong Guo <gch981213@gmail.com>
Link: https://lore.kernel.org/r/20200924152730.733243-3-gch981213@gmail.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent e7edd2cf

drivers/spi/spi-mtk-nor.c

+69 −7
Original line number Diff line number Diff line
@@ -168,10 +168,76 @@ static bool mtk_nor_match_read(const struct spi_mem_op *op) 
	return false;

}



static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)

static bool mtk_nor_match_prg(const struct spi_mem_op *op)

{

	size_t len;

	int tx_len, rx_len, prg_len, prg_left;



	// prg mode is spi-only.

	if ((op->cmd.buswidth > 1) || (op->addr.buswidth > 1) ||

	    (op->dummy.buswidth > 1) || (op->data.buswidth > 1))

		return false;



	tx_len = op->cmd.nbytes + op->addr.nbytes;



	if (op->data.dir == SPI_MEM_DATA_OUT) {

		// count dummy bytes only if we need to write data after it

		tx_len += op->dummy.nbytes;



		// leave at least one byte for data

		if (tx_len > MTK_NOR_REG_PRGDATA_MAX)

			return false;



		// if there's no addr, meaning adjust_op_size is impossible,

		// check data length as well.

		if ((!op->addr.nbytes) &&

		    (tx_len + op->data.nbytes > MTK_NOR_REG_PRGDATA_MAX + 1))

			return false;

	} else if (op->data.dir == SPI_MEM_DATA_IN) {

		if (tx_len > MTK_NOR_REG_PRGDATA_MAX + 1)

			return false;



		rx_len = op->data.nbytes;

		prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;

		if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)

			prg_left = MTK_NOR_REG_SHIFT_MAX + 1;

		if (rx_len > prg_left) {

			if (!op->addr.nbytes)

				return false;

			rx_len = prg_left;

		}



		prg_len = tx_len + op->dummy.nbytes + rx_len;

		if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)

			return false;

	} else {

		prg_len = tx_len + op->dummy.nbytes;

		if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)

			return false;

	}

	return true;

}



static void mtk_nor_adj_prg_size(struct spi_mem_op *op)

{

	int tx_len, tx_left, prg_left;



	tx_len = op->cmd.nbytes + op->addr.nbytes;

	if (op->data.dir == SPI_MEM_DATA_OUT) {

		tx_len += op->dummy.nbytes;

		tx_left = MTK_NOR_REG_PRGDATA_MAX + 1 - tx_len;

		if (op->data.nbytes > tx_left)

			op->data.nbytes = tx_left;

	} else if (op->data.dir == SPI_MEM_DATA_IN) {

		prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;

		if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)

			prg_left = MTK_NOR_REG_SHIFT_MAX + 1;

		if (op->data.nbytes > prg_left)

			op->data.nbytes = prg_left;

	}

}



static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)

{

	if (!op->data.nbytes)

		return 0;
@@ -200,11 +266,7 @@ static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) 
		}

	}



	len = MTK_NOR_PRG_MAX_SIZE - op->cmd.nbytes - op->addr.nbytes -

	      op->dummy.nbytes;

	if (op->data.nbytes > len)

		op->data.nbytes = len;



	mtk_nor_adj_prg_size(op);

	return 0;

}