Commits
Huang Shijie committed bab53fbf549
ENGR00227835 imx6q: gpmi: fix the warning when no NAND chip exits If there is no nand chip in the board, the kernel will prints out the following warning message: ------------[ cut here ]------------ WARNING: at arch/arm/plat-mxc/clock.c:63 clk_disable+0x48/0x90() clock enable/disable mismatch! clk apbh_dma_clk Modules linked in: [<80044f48>] (unwind_backtrace+0x0/0xfc) from [<80070ac0>] (warn_slowpath_common+0x4c/0x64) [<80070ac0>] (warn_slowpath_common+0x4c/0x64) from [<80070b6c>] (warn_slowpath_fmt+0x30/0x40) [<80070b6c>] (warn_slowpath_fmt+0x30/0x40) from [<8005ee60>] (clk_disable+0x48/0x90) [<8005ee60>] (clk_disable+0x48/0x90) from [<80255e48>] (dma_chan_put+0x4c/0x50) [<80255e48>] (dma_chan_put+0x4c/0x50) from [<80255f18>] (dma_release_channel+0x24/0x94) [<80255f18>] (dma_release_channel+0x24/0x94) from [<802ad8ec>] (release_resources+0x58/0x6c) [<802ad8ec>] (release_resources+0x58/0x6c) from [<80445964>] (gpmi_nand_probe+0x44c/0x4ec) [<80445964>] (gpmi_nand_probe+0x44c/0x4ec) from [<80281868>] (platform_drv_probe+0x18/0x1c) [<80281868>] (platform_drv_probe+0x18/0x1c) from [<80280590>] (driver_probe_device+0x98/0x1a4) [<80280590>] (driver_probe_device+0x98/0x1a4) from [<80280728>] (__driver_attach+0x8c/0x90) [<80280728>] (__driver_attach+0x8c/0x90) from [<8027fdd0>] (bus_for_each_dev+0x60/0x8c) [<8027fdd0>] (bus_for_each_dev+0x60/0x8c) from [<8027f75c>] (bus_add_driver+0x184/0x25c) [<8027f75c>] (bus_add_driver+0x184/0x25c) from [<80280d1c>] (driver_register+0x78/0x13c) [<80280d1c>] (driver_register+0x78/0x13c) from [<80022d80>] (gpmi_nand_init+0xc/0x3c) [<80022d80>] (gpmi_nand_init+0xc/0x3c) from [<80039478>] (do_one_initcall+0x30/0x16c) [<80039478>] (do_one_initcall+0x30/0x16c) from [<80008410>] (kernel_init+0x98/0x144) [<80008410>] (kernel_init+0x98/0x144) from [<8003ffb4>] (kernel_thread_exit+0x0/0x8) ---[ end trace c28d32057fe33a29 ]--- This mxs_dma_clk's usecount is not correctly changed which causes the kernel shows this warning. This patch adds proper clk_disable_unprepare/clk_prepare_enable in the mxs-dma driver to balance the mxs_dma_clk's usecount. Also put the mxs_dma_clk when the gpmi exits. Signed-off-by: Huang Shijie <b32955@freescale.com>