Re: [PATCH 2/5] spi: spi-ti-qspi: add mmap mode read support

From: Mark Brown
Date: Mon Sep 14 2015 - 14:27:23 EST


On Fri, Sep 04, 2015 at 01:59:59PM +0530, Vignesh R wrote:

> +static int ti_qspi_spi_mtd_mmap_read(struct spi_device *spi,
> + loff_t from, size_t len,
> + size_t *retlen, u_char *buf,
> + u8 read_opcode, u8 addr_width,
> + u8 dummy_bytes)
> +{
> + struct ti_qspi *qspi = spi_master_get_devdata(spi->master);
> + int ret = 0;
> +
> + spi_bus_lock(qspi->master);

I suspect I'm going to see the answer to this in another patch but the
fact that we're having to take this lock in a driver when it's an op the
core should be calling.

> + ret = pm_runtime_get_sync(qspi->dev);
> + if (ret < 0) {
> + dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
> + return ret;
> + }

This would be better outside the lock, there's no need to have the lock
before we power on and this fixes the fact that you don't release the
lock here.

> + memcpy(buf, (__force void *)(qspi->mmap_base + from), len);

The fact that you're having to cast here should be a warning that
there's someting wrong here. I think you're looking for
memcpy_fromio().

> @@ -479,6 +576,7 @@ static int ti_qspi_probe(struct platform_device *pdev)
> master->setup = ti_qspi_setup;
> master->auto_runtime_pm = true;
> master->transfer_one_message = ti_qspi_start_transfer_one;
> + master->spi_mtd_mmap_read = ti_qspi_spi_mtd_mmap_read;
> master->dev.of_node = pdev->dev.of_node;
> master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
> SPI_BPW_MASK(8);

Don't we need to map a resource somewhere?

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