diff options
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/host/octeon2-common.c | 38 |
1 files changed, 24 insertions, 14 deletions
diff --git a/drivers/usb/host/octeon2-common.c b/drivers/usb/host/octeon2-common.c index 72d672cfcf39..5a0feed03561 100644 --- a/drivers/usb/host/octeon2-common.c +++ b/drivers/usb/host/octeon2-common.c @@ -3,18 +3,19 @@ * License. See the file "COPYING" in the main directory of this archive * for more details. * - * Copyright (C) 2010 Cavium Networks + * Copyright (C) 2010, 2011 Cavium Networks */ #include <linux/module.h> +#include <linux/mutex.h> #include <linux/delay.h> -#include <asm/atomic.h> - #include <asm/octeon/octeon.h> #include <asm/octeon/cvmx-uctlx-defs.h> -static atomic_t octeon2_usb_clock_start_cnt = ATOMIC_INIT(0); +static DEFINE_MUTEX(octeon2_usb_clocks_mutex); + +static int octeon2_usb_clock_start_cnt; void octeon2_usb_clocks_start(void) { @@ -26,8 +27,12 @@ void octeon2_usb_clocks_start(void) int i; unsigned long io_clk_64_to_ns; - if (atomic_inc_return(&octeon2_usb_clock_start_cnt) != 1) - return; + + mutex_lock(&octeon2_usb_clocks_mutex); + + octeon2_usb_clock_start_cnt++; + if (octeon2_usb_clock_start_cnt != 1) + goto exit; io_clk_64_to_ns = 64000000000ull / octeon_get_io_clock_rate(); @@ -43,6 +48,13 @@ void octeon2_usb_clocks_start(void) /* Step 3: Configure the reference clock, PHY, and HCLK */ clk_rst_ctl.u64 = cvmx_read_csr(CVMX_UCTLX_CLK_RST_CTL(0)); + + /* + * If the UCTL looks like it has already been started, skip + * the initialization, otherwise bus errors are obtained. + */ + if (clk_rst_ctl.s.hrst) + goto end_clock; /* 3a */ clk_rst_ctl.s.p_por = 1; clk_rst_ctl.s.hrst = 0; @@ -158,6 +170,7 @@ void octeon2_usb_clocks_start(void) clk_rst_ctl.s.hrst = 1; cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64); +end_clock: /* Now we can set some other registers. */ for (i = 0; i <= 1; i++) { @@ -168,18 +181,15 @@ void octeon2_usb_clocks_start(void) cvmx_write_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0), port_ctl_status.u64); } +exit: + mutex_unlock(&octeon2_usb_clocks_mutex); } EXPORT_SYMBOL(octeon2_usb_clocks_start); void octeon2_usb_clocks_stop(void) { - union cvmx_uctlx_if_ena if_ena; - - if (atomic_dec_return(&octeon2_usb_clock_start_cnt) != 0) - return; - - if_ena.u64 = 0; - if_ena.s.en = 0; - cvmx_write_csr(CVMX_UCTLX_IF_ENA(0), if_ena.u64); + mutex_lock(&octeon2_usb_clocks_mutex); + octeon2_usb_clock_start_cnt--; + mutex_unlock(&octeon2_usb_clocks_mutex); } EXPORT_SYMBOL(octeon2_usb_clocks_stop); |