clk: imx: use sign_extend32() and abs()

Commit Message

Martin Kepplinger-Novakovic Sept. 29, 2015, 11:32 a.m. UTC

This simplifies the given function by getting rid of the manual
sign extension as well as saving an absolute value in an extra
variable.

Signed-off-by: Martin Kepplinger <[e-mail]>
---
built and run, but please review.

                     martin


 drivers/clk/imx/clk-pllv2.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

Comments

Stephen Boyd Oct. 1, 2015, 11:39 p.m. UTC | #1

On 09/29, Martin Kepplinger wrote:
> This simplifies the given function by getting rid of the manual
> sign extension as well as saving an absolute value in an extra
> variable.
> 
> Signed-off-by: Martin Kepplinger <[e-mail]>
> ---

Applied to clk-next

Patch

diff --git a/drivers/clk/imx/clk-pllv2.c b/drivers/clk/imx/clk-pllv2.c
index 20889d5..b18f875 100644
--- a/drivers/clk/imx/clk-pllv2.c
+++ b/drivers/clk/imx/clk-pllv2.c
@@ -77,7 +77,7 @@  struct clk_pllv2 {
 static unsigned long __clk_pllv2_recalc_rate(unsigned long parent_rate,
 		u32 dp_ctl, u32 dp_op, u32 dp_mfd, u32 dp_mfn)
 {
-	long mfi, mfn, mfd, pdf, ref_clk, mfn_abs;
+	long mfi, mfn, mfd, pdf, ref_clk;
 	unsigned long dbl;
 	s64 temp;
 
@@ -87,19 +87,15 @@  static unsigned long __clk_pllv2_recalc_rate(unsigned long parent_rate,
 	mfi = (dp_op & MXC_PLL_DP_OP_MFI_MASK) >> MXC_PLL_DP_OP_MFI_OFFSET;
 	mfi = (mfi <= 5) ? 5 : mfi;
 	mfd = dp_mfd & MXC_PLL_DP_MFD_MASK;
-	mfn = mfn_abs = dp_mfn & MXC_PLL_DP_MFN_MASK;
-	/* Sign extend to 32-bits */
-	if (mfn >= 0x04000000) {
-		mfn |= 0xFC000000;
-		mfn_abs = -mfn;
-	}
+	mfn = dp_mfn & MXC_PLL_DP_MFN_MASK;
+	mfn = sign_extend32(mfn, 26);
 
 	ref_clk = 2 * parent_rate;
 	if (dbl != 0)
 		ref_clk *= 2;
 
 	ref_clk /= (pdf + 1);
-	temp = (u64) ref_clk * mfn_abs;
+	temp = (u64) ref_clk * abs(mfn);
 	do_div(temp, mfd + 1);
 	if (mfn < 0)
 		temp = -temp;