Make use of the clk framework to give us a rate as close to 50MHz as possible.
Signed-off-by: Manuel Lauss <[email protected]> --- arch/mips/alchemy/devboards/db1200.c | 45 ++++++++++++++++-------------------- 1 file changed, 20 insertions(+), 25 deletions(-) diff --git a/arch/mips/alchemy/devboards/db1200.c b/arch/mips/alchemy/devboards/db1200.c index 8c71cde..f255586 100644 --- a/arch/mips/alchemy/devboards/db1200.c +++ b/arch/mips/alchemy/devboards/db1200.c @@ -18,6 +18,7 @@ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ +#include <linux/clk.h> #include <linux/dma-mapping.h> #include <linux/gpio.h> #include <linux/i2c.h> @@ -129,7 +130,6 @@ static int __init db1200_detect_board(void) int __init db1200_board_setup(void) { - unsigned long freq0, clksrc, div, pfc; unsigned short whoami; if (db1200_detect_board()) @@ -149,30 +149,6 @@ int __init db1200_board_setup(void) " Board-ID %d Daughtercard ID %d\n", get_system_type(), (whoami >> 4) & 0xf, (whoami >> 8) & 0xf, whoami & 0xf); - /* SMBus/SPI on PSC0, Audio on PSC1 */ - pfc = AU1X_RDSYS(AU1000_SYS_PINFUNC); - pfc &= ~(SYS_PINFUNC_P0A | SYS_PINFUNC_P0B); - pfc &= ~(SYS_PINFUNC_P1A | SYS_PINFUNC_P1B | SYS_PINFUNC_FS3); - pfc |= SYS_PINFUNC_P1C; /* SPI is configured later */ - AU1X_WRSYS(pfc, AU1000_SYS_PINFUNC); - - /* Clock configurations: PSC0: ~50MHz via Clkgen0, derived from - * CPU clock; all other clock generators off/unused. - */ - div = (get_au1x00_speed() + 25000000) / 50000000; - if (div & 1) - div++; - div = ((div >> 1) - 1) & 0xff; - - freq0 = div << SYS_FC_FRDIV0_BIT; - AU1X_WRSYS(freq0, AU1000_SYS_FREQCTRL0); - freq0 |= SYS_FC_FE0; /* enable F0 */ - AU1X_WRSYS(freq0, AU1000_SYS_FREQCTRL0); - - /* psc0_intclk comes 1:1 from F0 */ - clksrc = SYS_CS_MUX_FQ0 << SYS_CS_ME0_BIT; - AU1X_WRSYS(clksrc, AU1000_SYS_CLKSRC); - return 0; } @@ -845,6 +821,7 @@ int __init db1200_dev_setup(void) unsigned long pfc; unsigned short sw; int swapped, bid; + struct clk *c; bid = BCSR_WHOAMI_BOARD(bcsr_read(BCSR_WHOAMI)); if ((bid == BCSR_WHOAMI_PB1200_DDR1) || @@ -857,6 +834,24 @@ int __init db1200_dev_setup(void) irq_set_irq_type(AU1200_GPIO7_INT, IRQ_TYPE_LEVEL_LOW); bcsr_init_irq(DB1200_INT_BEGIN, DB1200_INT_END, AU1200_GPIO7_INT); + /* SMBus/SPI on PSC0, Audio on PSC1 */ + pfc = AU1X_RDSYS(AU1000_SYS_PINFUNC); + pfc &= ~(SYS_PINFUNC_P0A | SYS_PINFUNC_P0B); + pfc &= ~(SYS_PINFUNC_P1A | SYS_PINFUNC_P1B | SYS_PINFUNC_FS3); + pfc |= SYS_PINFUNC_P1C; /* SPI is configured later */ + AU1X_WRSYS(pfc, AU1000_SYS_PINFUNC); + + /* get 50MHz for I2C driver on PSC0 */ + c = clk_get(NULL, "psc0_intclk"); + if (!IS_ERR(c)) { + pfc = clk_round_rate(c, 50000000); + if ((pfc < 1) || (abs(50000000 - pfc) > 2500000)) + pr_warn("DB1200: cant get I2C close to 50MHz\n"); + else + clk_set_rate(c, pfc); + clk_put(c); + } + /* insert/eject pairs: one of both is always screaming. To avoid * issues they must not be automatically enabled when initially * requested. -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
