dma: dw: improve comparison with ~0

In general ~0 does not fit some integer types. Let's do a helper to make a
comparison with that constant properly.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index eea479c121736e20c6e52f71059df1b4e14a364b..1ed9a9c9194afb69825653a1029b3169ff8c0aa1 100644 (file)
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -37,16 +37,22 @@
  * which does not support descriptor writeback.
  */
 
+static inline bool is_request_line_unset(struct dw_dma_chan *dwc)
+{
+       return dwc->request_line == (typeof(dwc->request_line))~0;
+}
+
 static inline void dwc_set_masters(struct dw_dma_chan *dwc)
 {
        struct dw_dma *dw = to_dw_dma(dwc->chan.device);
        struct dw_dma_slave *dws = dwc->chan.private;
        unsigned char mmax = dw->nr_masters - 1;
 
-       if (dwc->request_line == ~0) {
-               dwc->src_master = min_t(unsigned char, mmax, dwc_get_sms(dws));
-               dwc->dst_master = min_t(unsigned char, mmax, dwc_get_dms(dws));
-       }
+       if (!is_request_line_unset(dwc))
+               return;
+
+       dwc->src_master = min_t(unsigned char, mmax, dwc_get_sms(dws));
+       dwc->dst_master = min_t(unsigned char, mmax, dwc_get_dms(dws));
 }
 
 #define DWC_DEFAULT_CTLLO(_chan) ({                            \
@@ -984,7 +990,7 @@ set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
        dwc->direction = sconfig->direction;
 
        /* Take the request line from slave_id member */
-       if (dwc->request_line == ~0)
+       if (is_request_line_unset(dwc))
                dwc->request_line = sconfig->slave_id;
 
        convert_burst(&dwc->dma_sconfig.src_maxburst);