Hi Dan, Am Donnerstag, 31. Juli 2014, 13:39:36 schrieb Dan Carpenter: > Hello Heiko Stuebner, > > The patch af99a7507469: "pinctrl: Add pinctrl-s3c24xx driver" from > May 21, 2013, leads to the following static checker warning: > > drivers/pinctrl/samsung/pinctrl-s3c24xx.c:188 s3c24xx_eint_type() > warn: are you sure the precedence is correct here? > > drivers/pinctrl/samsung/pinctrl-s3c24xx.c > 186 /* Set up interrupt trigger */ > 187 reg = d->virt_base + EINT_REG(index); > 188 shift = EINT_OFFS(index); > 189 > > EINT_OFFS() is defined with two different precedences. One of them is > probably wrong and it's probably this one here that does the MOD > operation first followed by the multiply. > > #define EINT_OFFS(i) ((i) % EINT_MAX_PER_GROUP * 4) > #define EINT_OFFS(i) ((i) % (2 * EINT_MAX_PER_GROUP)) I suppose the other EINT_OFFS definition ((i) % (2 * EINT_MAX_PER_GROUP)) is from pinctrl-64xx.c, right? On the s3c24xx, the eints are arranged in a set of registers: eint0 bits [2:0] eint1 bits [6:4] ... eint7 bits [30:28] (next register): eint8 bits [2:0] ... eint15 bits [30:28] ... EINT_MAX_PER_GROUP is of course 8, so for example eint15 % 8 = 7 7 * 4 = 28 ... the correct bit offset in the register. The eint layout on the s3c64xx is slightly different, so the offset calculation is likely too. Heiko -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
