On Tue, Dec 20, 2022 at 04:48:06PM +0000, Hanna Hawa wrote: > From: Lareine Khawaly <lareine@xxxxxxxxxx> > > In functions i2c_dw_scl_lcnt() and i2c_dw_scl_hcnt() may have overflow > by depending on the values of the given parameters including the ic_clk. > For example in our use case where ic_clk is larger than one million, > multiplication of ic_clk * 4700 will result in 32 bit overflow. > > Add cast of u64 to the calculation to avoid multiplication overflow, and > use the corresponding define for divide. ... > - return DIV_ROUND_CLOSEST(ic_clk * tSYMBOL, MICRO) - 8 + offset; > + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * tSYMBOL, MICRO) - 8 + > + offset; Broken indentation. ... > - return DIV_ROUND_CLOSEST(ic_clk * (tSYMBOL + tf), MICRO) - 3 + offset; > + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), > + MICRO) - 3 + offset; I would still go with 'MICRO) -' part to be on the previous line despite being over 80, this is logical split which increases readability. > - return DIV_ROUND_CLOSEST(ic_clk * (tLOW + tf), MICRO) - 1 + offset; > + return DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) - 1 + > + offset; Broken indentation. -- With Best Regards, Andy Shevchenko
