Re: [PATCH 4/8] gpio: pcie-idio-24: Implement get_multiple callback
Hi William,
I love your patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v4.16-rc5 next-20180313]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system]
url:
https://github.com/0day-ci/linux/commits/William-Breathitt-Gray/Implement-get_multiple-for-ACCES-and-PC104-drivers/20180313-202244
config: x86_64-randconfig-x014-201810 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
drivers//gpio/gpio-pcie-idio-24.c: In function 'idio_24_gpio_get_multiple':
>> drivers//gpio/gpio-pcie-idio-24.c:252:35: warning: 'port_state' may be used
>> uninitialized in this function [-Wmaybe-uninitialized]
bits[BIT_WORD(i)] |= port_state << bit_word_offset;
~~~^~
vim +/port_state +252 drivers//gpio/gpio-pcie-idio-24.c
195
196 static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
197 unsigned long *mask, unsigned long *bits)
198 {
199 struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
200 struct idio_24_gpio_reg __iomem *const reg = idio24gpio->reg;
201 unsigned int i;
202 const unsigned int gpio_reg_size = 8;
203 unsigned int bit_word_offset;
204 unsigned int bits_mask;
205 const unsigned long reg_mask = GENMASK(gpio_reg_size, 0);
206 unsigned long port_state;
207 const unsigned long out_mode_mask = BIT(1);
208
209 /* clear bits array to a clean slate */
210 for (i = 0; i < chip->ngpio; i += BITS_PER_LONG)
211 bits[i / BITS_PER_LONG] = 0;
212
213 /* get bits are evaluated a gpio register size at a time */
214 for (i = 0; i < chip->ngpio; i += gpio_reg_size) {
215 bit_word_offset = i % BITS_PER_LONG;
216 bits_mask = mask[BIT_WORD(i)] & (reg_mask <<
bit_word_offset);
217 if (!bits_mask) {
218 /* no get bits in this register so skip to next
one */
219 continue;
220 }
221
222 /* read bits from current gpio register */
223 switch (i / gpio_reg_size) {
224 case 0:
225 port_state = ioread8(>out0_7);
226 break;
227 case 1:
228 port_state = ioread8(>out8_15);
229 break;
230 case 2:
231 port_state = ioread8(>out16_23);
232 break;
233 case 3:
234 port_state = ioread8(>in0_7);
235 break;
236 case 4:
237 port_state = ioread8(>in8_15);
238 break;
239 case 5:
240 port_state = ioread8(>in16_23);
241 break;
242 case 6:
243 /* TTL/CMOS Outputs/Inputs */
244 if (ioread8(>ctl) & out_mode_mask)
245 port_state = ioread8(>ttl_out0_7);
246 else
247 port_state = ioread8(>ttl_in0_7);
248 break;
249 }
250
251 /* store acquired bits */
> 252 bits[BIT_WORD(i)] |= port_state << bit_word_offset;
253 }
254
255 return 0;
256 }
257
---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
.config.gz
Description: application/gzip
Re: [PATCH 4/8] gpio: pcie-idio-24: Implement get_multiple callback
Hi William,
I love your patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v4.16-rc5 next-20180313]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system]
url:
https://github.com/0day-ci/linux/commits/William-Breathitt-Gray/Implement-get_multiple-for-ACCES-and-PC104-drivers/20180313-202244
config: x86_64-randconfig-x014-201810 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All warnings (new ones prefixed by >>):
drivers//gpio/gpio-pcie-idio-24.c: In function 'idio_24_gpio_get_multiple':
>> drivers//gpio/gpio-pcie-idio-24.c:252:35: warning: 'port_state' may be used
>> uninitialized in this function [-Wmaybe-uninitialized]
bits[BIT_WORD(i)] |= port_state << bit_word_offset;
~~~^~
vim +/port_state +252 drivers//gpio/gpio-pcie-idio-24.c
195
196 static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
197 unsigned long *mask, unsigned long *bits)
198 {
199 struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
200 struct idio_24_gpio_reg __iomem *const reg = idio24gpio->reg;
201 unsigned int i;
202 const unsigned int gpio_reg_size = 8;
203 unsigned int bit_word_offset;
204 unsigned int bits_mask;
205 const unsigned long reg_mask = GENMASK(gpio_reg_size, 0);
206 unsigned long port_state;
207 const unsigned long out_mode_mask = BIT(1);
208
209 /* clear bits array to a clean slate */
210 for (i = 0; i < chip->ngpio; i += BITS_PER_LONG)
211 bits[i / BITS_PER_LONG] = 0;
212
213 /* get bits are evaluated a gpio register size at a time */
214 for (i = 0; i < chip->ngpio; i += gpio_reg_size) {
215 bit_word_offset = i % BITS_PER_LONG;
216 bits_mask = mask[BIT_WORD(i)] & (reg_mask <<
bit_word_offset);
217 if (!bits_mask) {
218 /* no get bits in this register so skip to next
one */
219 continue;
220 }
221
222 /* read bits from current gpio register */
223 switch (i / gpio_reg_size) {
224 case 0:
225 port_state = ioread8(>out0_7);
226 break;
227 case 1:
228 port_state = ioread8(>out8_15);
229 break;
230 case 2:
231 port_state = ioread8(>out16_23);
232 break;
233 case 3:
234 port_state = ioread8(>in0_7);
235 break;
236 case 4:
237 port_state = ioread8(>in8_15);
238 break;
239 case 5:
240 port_state = ioread8(>in16_23);
241 break;
242 case 6:
243 /* TTL/CMOS Outputs/Inputs */
244 if (ioread8(>ctl) & out_mode_mask)
245 port_state = ioread8(>ttl_out0_7);
246 else
247 port_state = ioread8(>ttl_in0_7);
248 break;
249 }
250
251 /* store acquired bits */
> 252 bits[BIT_WORD(i)] |= port_state << bit_word_offset;
253 }
254
255 return 0;
256 }
257
---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
.config.gz
Description: application/gzip
