From: Hemanth V <[email protected]> This patch adds context save/restore feature to McSPI driver. This has been tested by instrumenting the driver code i.e by adding a McSPI softreset in omap2_mcspi_disable_clocks function.
This patch includes review comment fixes Signed-off-by: Hemanth V <[email protected]> --- drivers/spi/omap2_mcspi.c | 94 ++++++++++++++++++++++++++++++++++++---------- 1 files changed, 74 insertions(+), 20 deletions(-) Index: linux-omap-2.6/drivers/spi/omap2_mcspi.c =================================================================== --- linux-omap-2.6.orig/drivers/spi/omap2_mcspi.c +++ linux-omap-2.6/drivers/spi/omap2_mcspi.c @@ -41,6 +41,9 @@ #define OMAP2_MCSPI_MAX_FREQ 48000000 +/* OMAP2 has 3 SPI controllers, while OMAP3 has 4 */ +#define OMAP2_MCSPI_MAX_CTRL 4 + #define OMAP2_MCSPI_REVISION 0x00 #define OMAP2_MCSPI_SYSCONFIG 0x10 #define OMAP2_MCSPI_SYSSTATUS 0x14 @@ -133,6 +136,15 @@ int word_len; }; +struct omap2_mcspi_regs { + u32 sysconfig; + u32 modulctrl; + u32 chconf0; + u32 wakeupenable; +}; + +static struct omap2_mcspi_regs omap2_mcspi_ctx[OMAP2_MCSPI_MAX_CTRL]; + static struct workqueue_struct *omap2_mcspi_wq; #define MOD_REG_BIT(val, mask, set) do { \ @@ -217,6 +229,45 @@ MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_MS, 0); MOD_REG_BIT(l, OMAP2_MCSPI_MODULCTRL_SINGLE, 1); mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l); + + omap2_mcspi_ctx[master->bus_num - 1].modulctrl = l; +} + +static void omap2_mcspi_restore_ctx(struct omap2_mcspi *mcspi) +{ + struct spi_master *spi_cntrl; + spi_cntrl = mcspi->master; + + /*McSPI : context restore */ + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_MODULCTRL, + omap2_mcspi_ctx[spi_cntrl->bus_num - 1].modulctrl); + + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_SYSCONFIG, + omap2_mcspi_ctx[spi_cntrl->bus_num - 1].sysconfig); + + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_CHCONF0, + omap2_mcspi_ctx[spi_cntrl->bus_num - 1].chconf0); + + + mcspi_write_reg(spi_cntrl, OMAP2_MCSPI_WAKEUPENABLE, + omap2_mcspi_ctx[spi_cntrl->bus_num - 1].wakeupenable); +} +static void omap2_mcspi_disable_clocks(struct omap2_mcspi *mcspi) +{ + clk_disable(mcspi->ick); + clk_disable(mcspi->fck); +} + +static int omap2_mcspi_enable_clocks(struct omap2_mcspi *mcspi) +{ + if (clk_enable(mcspi->ick)) + return -ENODEV; + if (clk_enable(mcspi->fck)) + return -ENODEV; + + omap2_mcspi_restore_ctx(mcspi); + + return 0; } static unsigned @@ -486,10 +537,12 @@ { struct omap2_mcspi_cs *cs = spi->controller_state; struct omap2_mcspi *mcspi; + struct spi_master *spi_cntrl; u32 l = 0, div = 0; u8 word_len = spi->bits_per_word; mcspi = spi_master_get_devdata(spi->master); + spi_cntrl = mcspi->master; if (t != NULL && t->bits_per_word) word_len = t->bits_per_word; @@ -537,6 +590,8 @@ mcspi_write_cs_reg(spi, OMAP2_MCSPI_CHCONF0, l); + omap2_mcspi_ctx[spi_cntrl->bus_num - 1].chconf0 = l; + dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n", OMAP2_MCSPI_MAX_FREQ / (1 << div), (spi->mode & SPI_CPHA) ? "trailing" : "leading", @@ -649,11 +704,11 @@ return ret; } - clk_enable(mcspi->ick); - clk_enable(mcspi->fck); + if (omap2_mcspi_enable_clocks(mcspi)) + return -ENODEV; + ret = omap2_mcspi_setup_transfer(spi, NULL); - clk_disable(mcspi->fck); - clk_disable(mcspi->ick); + omap2_mcspi_disable_clocks(mcspi); return ret; } @@ -685,8 +740,8 @@ mcspi = container_of(work, struct omap2_mcspi, work); spin_lock_irq(&mcspi->lock); - clk_enable(mcspi->ick); - clk_enable(mcspi->fck); + if (omap2_mcspi_enable_clocks(mcspi)) + return; /* We only enable one channel at a time -- the one whose message is * at the head of the queue -- although this controller would gladly @@ -788,8 +843,7 @@ spin_lock_irq(&mcspi->lock); } - clk_disable(mcspi->fck); - clk_disable(mcspi->ick); + omap2_mcspi_disable_clocks(mcspi); spin_unlock_irq(&mcspi->lock); } @@ -877,8 +931,8 @@ struct spi_master *master = mcspi->master; u32 tmp; - clk_enable(mcspi->ick); - clk_enable(mcspi->fck); + if (omap2_mcspi_enable_clocks(mcspi)) + return -1; mcspi_write_reg(master, OMAP2_MCSPI_SYSCONFIG, OMAP2_MCSPI_SYSCONFIG_SOFTRESET); @@ -886,18 +940,18 @@ tmp = mcspi_read_reg(master, OMAP2_MCSPI_SYSSTATUS); } while (!(tmp & OMAP2_MCSPI_SYSSTATUS_RESETDONE)); - mcspi_write_reg(master, OMAP2_MCSPI_SYSCONFIG, - OMAP2_MCSPI_SYSCONFIG_AUTOIDLE | - OMAP2_MCSPI_SYSCONFIG_ENAWAKEUP | - OMAP2_MCSPI_SYSCONFIG_SMARTIDLE); - - mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, - OMAP2_MCSPI_WAKEUPENABLE_WKEN); + tmp = OMAP2_MCSPI_SYSCONFIG_AUTOIDLE | + OMAP2_MCSPI_SYSCONFIG_ENAWAKEUP | + OMAP2_MCSPI_SYSCONFIG_SMARTIDLE; + mcspi_write_reg(master, OMAP2_MCSPI_SYSCONFIG, tmp); + omap2_mcspi_ctx[master->bus_num - 1].sysconfig = tmp; + + tmp = OMAP2_MCSPI_WAKEUPENABLE_WKEN; + mcspi_write_reg(master, OMAP2_MCSPI_WAKEUPENABLE, tmp); + omap2_mcspi_ctx[master->bus_num - 1].wakeupenable = tmp; omap2_mcspi_set_master_mode(master); - - clk_disable(mcspi->fck); - clk_disable(mcspi->ick); + omap2_mcspi_disable_clocks(mcspi); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
