Re: [2/2] spi: Add SPI master controller for OCTEON SOCs.

From: David Daney
Date: Tue Aug 21 2012 - 16:38:05 EST


On 08/21/2012 12:49 PM, Guenter Roeck wrote:
On Fri, May 11, 2012 at 08:34:46PM -0000, David Daney wrote:
From: David Daney <david.daney@xxxxxxxxxx>

Add the driver, link it into the kbuild system and provide device tree
binding documentation.

Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
Acked-by: Grant Likely <grant.likely@xxxxxxxxxxxx>

[ ... ]

+
+static int __devexit octeon_spi_remove(struct platform_device *pdev)
+{
+ struct octeon_spi *p = platform_get_drvdata(pdev);
+ struct spi_master *master = p->my_master;
+
+ spi_unregister_master(master);
+

I know it is a bit late, but ...

In this case, just in time. I am now finally getting back to fixing the issues with this driver, and looking to merging it in the near future.

David Daney


The call to spi_unregister_master() frees the memory associated with master,
ie 'p', and the spi_master_put() below without matching spi_master_get() is
unnecessary/wrong. One possible fix would be to use

struct spi_master *master = spi_master_get(p->my_master);

above. That protects master and p while it is still being used, and makes use
of the call to spi_master_put() below. Another option might be to move
cvmx_write_csr() ahead of the call to spi_unregister_master() and drop the
call to spi_master_put().

Guenter

+ /* Clear the CSENA* and put everything in a known state. */
+ cvmx_write_csr(p->register_base + OCTEON_SPI_CFG, 0);
+ spi_master_put(master);
+ return 0;
+}
+



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