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    SubjectRe: [PATCH 15/19] mc13xxx: mfd_cell is now implicitly available to drivers
    Hello,

    On Fri, Feb 04, 2011 at 10:34:58AM +0100, Uwe Kleine-König wrote:
    > And I think this patch has a conceptual problem, too. In my opionion
    > platform_data is the point to hand over platform specific data to a
    > driver. driver_data is something that is private to the driver and has
    > to be considered opaque for the platform. The driver was sort of OK
    > before ...

    So consequently I propose the patch below. I'm sure that a few drivers
    will break, but IMHO that's OK.

    And by the way, did you know that platform_set_drvdata can fail and you
    have no nice way to notice that but to do:

    dev_set_drvdata(dev, mypreciousdata);
    if (dev_get_drvdata(dev) != mypreciousdata)
    goto fail;
    Best regards
    Uwe

    ------>8-----------
    From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
    Date: Fri, 4 Feb 2011 11:00:42 +0100
    Subject: [PATCH] MFD: platform_set_drvdata should be only called by drivers
    driver data is data private to drivers so it's not a point to hand over
    data to the driver by the platform. That's what platform_data is available
    for. The only place platform_set_drvdata should be called is in a
    driver that has bound the device in question.

    Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
    ---
    drivers/mfd/mfd-core.c | 1 -
    include/linux/mfd/core.h | 3 ---
    2 files changed, 0 insertions(+), 4 deletions(-)
    diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
    index d83ad0f..8d06e0c 100644
    --- a/drivers/mfd/mfd-core.c
    +++ b/drivers/mfd/mfd-core.c
    @@ -37,7 +37,6 @@ static int mfd_add_device(struct device *parent, int id,
    goto fail_device;

    pdev->dev.parent = parent;
    - platform_set_drvdata(pdev, cell->driver_data);

    if (cell->data_size) {
    ret = platform_device_add_data(pdev,
    diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
    index 835996e..88bb7b5 100644
    --- a/include/linux/mfd/core.h
    +++ b/include/linux/mfd/core.h
    @@ -30,9 +30,6 @@ struct mfd_cell {
    int (*suspend)(struct platform_device *dev);
    int (*resume)(struct platform_device *dev);

    - /* driver-specific data for MFD-aware "cell" drivers */
    - void *driver_data;
    -
    /* platform_data can be used to either pass data to "generic"
    driver or as a hook to mfd_cell for the "cell" drivers */
    void *platform_data;
    --
    1.7.2.3
    --
    Pengutronix e.K. | Uwe Kleine-König |
    Industrial Linux Solutions | http://www.pengutronix.de/ |
    --
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