From b42ca86ad605eb3e3f26618eed35ac6ff7435964 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Wed, 23 Mar 2016 15:37:04 -0700 Subject: [PATCH] staging: comedi: ni_tio: remove BUG() checks for ni_tio_get_clock_src() This function calls some helper functions to convert the counter variant specific clock select bits into the generic enum ni_gpct_clock_source_bits equivelent. These helper functions currently BUG() if the clock select bits are invalid. It then calls ni_tio_clock_period_ps() to figure out the clock period based on the generic clock source. This function could also BUG() if the prescale bits are invalid. In reality this should never happen but refactor the code to return -EINVAL instead and remove the BUG() checks. These functions are also called by ni_tio_set_sync_mode(). When this function is called by ni_tio_set_clock_src() the counter select bits have already been validated. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/ni_tio.c | 60 ++++++++++++++----------- 1 file changed, 35 insertions(+), 25 deletions(-) diff --git a/drivers/staging/comedi/drivers/ni_tio.c b/drivers/staging/comedi/drivers/ni_tio.c index 9ce3a9a92a9a..7043eb0543f6 100644 --- a/drivers/staging/comedi/drivers/ni_tio.c +++ b/drivers/staging/comedi/drivers/ni_tio.c @@ -183,8 +183,9 @@ static void ni_tio_reset_count_and_disarm(struct ni_gpct *counter) ni_tio_write(counter, GI_RESET(cidx), NITIO_RESET_REG(cidx)); } -static u64 ni_tio_clock_period_ps(const struct ni_gpct *counter, - unsigned int generic_clock_source) +static int ni_tio_clock_period_ps(const struct ni_gpct *counter, + unsigned int generic_clock_source, + u64 *period_ps) { u64 clock_period_ps; @@ -219,10 +220,10 @@ static u64 ni_tio_clock_period_ps(const struct ni_gpct *counter, clock_period_ps *= 8; break; default: - BUG(); - break; + return -EINVAL; } - return clock_period_ps; + *period_ps = clock_period_ps; + return 0; } static void ni_tio_set_bits_transient(struct ni_gpct *counter, @@ -304,7 +305,8 @@ static unsigned int ni_tio_clock_src_modifiers(const struct ni_gpct *counter) return bits; } -static unsigned int ni_m_series_clock_src_select(const struct ni_gpct *counter) +static int ni_m_series_clock_src_select(const struct ni_gpct *counter, + unsigned int *clk_src) { struct ni_gpct_device *counter_dev = counter->counter_dev; unsigned int cidx = counter->counter_index; @@ -362,14 +364,15 @@ static unsigned int ni_m_series_clock_src_select(const struct ni_gpct *counter) } if (i <= NI_M_MAX_PFI_CHAN) break; - BUG(); - break; + return -EINVAL; } clock_source |= ni_tio_clock_src_modifiers(counter); - return clock_source; + *clk_src = clock_source; + return 0; } -static unsigned int ni_660x_clock_src_select(const struct ni_gpct *counter) +static int ni_660x_clock_src_select(const struct ni_gpct *counter, + unsigned int *clk_src) { unsigned int clock_source = 0; unsigned int cidx = counter->counter_index; @@ -419,23 +422,23 @@ static unsigned int ni_660x_clock_src_select(const struct ni_gpct *counter) } if (i <= NI_660X_MAX_SRC_PIN) break; - BUG(); - break; + return -EINVAL; } clock_source |= ni_tio_clock_src_modifiers(counter); - return clock_source; + *clk_src = clock_source; + return 0; } -static unsigned int -ni_tio_generic_clock_src_select(const struct ni_gpct *counter) +static int ni_tio_generic_clock_src_select(const struct ni_gpct *counter, + unsigned int *clk_src) { switch (counter->counter_dev->variant) { case ni_gpct_variant_e_series: case ni_gpct_variant_m_series: default: - return ni_m_series_clock_src_select(counter); + return ni_m_series_clock_src_select(counter, clk_src); case ni_gpct_variant_660x: - return ni_660x_clock_src_select(counter); + return ni_660x_clock_src_select(counter, clk_src); } } @@ -448,6 +451,7 @@ static void ni_tio_set_sync_mode(struct ni_gpct *counter) unsigned int bits = 0; unsigned int reg; unsigned int mode; + unsigned int clk_src; u64 ps; bool force_alt_sync; @@ -478,8 +482,8 @@ static void ni_tio_set_sync_mode(struct ni_gpct *counter) break; } - ps = ni_tio_clock_period_ps(counter, - ni_tio_generic_clock_src_select(counter)); + ni_tio_generic_clock_src_select(counter, &clk_src); + ni_tio_clock_period_ps(counter, clk_src, &ps); /* * It's not clear what we should do if clock_period is unknown, so we @@ -800,16 +804,22 @@ static int ni_tio_set_clock_src(struct ni_gpct *counter, return 0; } -static void ni_tio_get_clock_src(struct ni_gpct *counter, - unsigned int *clock_source, - unsigned int *period_ns) +static int ni_tio_get_clock_src(struct ni_gpct *counter, + unsigned int *clock_source, + unsigned int *period_ns) { u64 temp64; + int ret; - *clock_source = ni_tio_generic_clock_src_select(counter); - temp64 = ni_tio_clock_period_ps(counter, *clock_source); + ret = ni_tio_generic_clock_src_select(counter, clock_source); + if (ret) + return ret; + ret = ni_tio_clock_period_ps(counter, *clock_source, &temp64); + if (ret) + return ret; do_div(temp64, 1000); /* ps to ns */ *period_ns = temp64; + return 0; } static int ni_660x_set_gate(struct ni_gpct *counter, unsigned int gate_source) @@ -1320,7 +1330,7 @@ int ni_tio_insn_config(struct comedi_device *dev, ret = ni_tio_set_clock_src(counter, data[1], data[2]); break; case INSN_CONFIG_GET_CLOCK_SRC: - ni_tio_get_clock_src(counter, &data[1], &data[2]); + ret = ni_tio_get_clock_src(counter, &data[1], &data[2]); break; case INSN_CONFIG_SET_GATE_SRC: ret = ni_tio_set_gate_src(counter, data[1], data[2]); -- 2.20.1