[kbuild-all] Re: [PATCH] rtc: rs5c372: Fix read the time from RTC is illegal When reading time from an uninitialized RTC chip, The value may be illegal

Hi, Thank you for the patch! Yet something to improve: [auto build test ERROR on abelloni/rtc-next] [also build test ERROR on v5.13-rc2 next-20210521] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/qxj511mail-gmail-com/rtc-rs5c372... base: https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git rtc-next config: x86_64-randconfig-s031-20210522 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-341-g8af24329-dirty # https://github.com/0day-ci/linux/commit/62c495535e38dc184558713e6c007071f... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review qxj511mail-gmail-com/rtc-rs5c372-Fix-read-the-time-from-RTC-is-illegal-When-reading-time-from-an-uninitialized-RTC-chip-The-value-may-be-ille/20210522-202320 git checkout 62c495535e38dc184558713e6c007071f50f516c # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): drivers/rtc/rtc-rs5c372.c: In function 'rs5c372_rtc_read_time': 261 | rs5c372_rtc_set_time(dev, tm); | ^~~~~~~~~~~~~~~~~~~~ | rs5c372_rtc_read_time drivers/rtc/rtc-rs5c372.c: At top level: 273 | static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm) | ^~~~~~~~~~~~~~~~~~~~ drivers/rtc/rtc-rs5c372.c:261:3: note: previous implicit declaration of 'rs5c372_rtc_set_time' was here 261 | rs5c372_rtc_set_time(dev, tm); | ^~~~~~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +261 drivers/rtc/rtc-rs5c372.c 208 209 static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm) 210 { 211 struct i2c_client *client = to_i2c_client(dev); 212 struct rs5c372 *rs5c = i2c_get_clientdata(client); 213 int status = rs5c_get_regs(rs5c); 214 unsigned char ctrl2 = rs5c->regs[RS5C_REG_CTRL2]; 215 int flags_utime = 0; 216 217 if (status < 0) 218 return status; 219 220 switch (rs5c->type) { 221 case rtc_r2025sd: 222 case rtc_r2221tl: 223 if ((rs5c->type == rtc_r2025sd && !(ctrl2 & R2x2x_CTRL2_XSTP)) || 224 (rs5c->type == rtc_r2221tl && (ctrl2 & R2x2x_CTRL2_XSTP))) { 225 dev_warn(&client->dev, "rtc oscillator interruption detected. Please reset the rtc clock.\n"); 226 return -EINVAL; 227 } 228 break; 229 default: 230 if (ctrl2 & RS5C_CTRL2_XSTP) { 231 dev_warn(&client->dev, "rtc oscillator interruption detected. Please reset the rtc clock.\n"); 232 return -EINVAL; 233 } 234 } 235 236 tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f); 237 tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f); 238 tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]); 239 240 tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07); 241 tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f); 242 243 if (tm->tm_mday < 1) { 244 // The value read from the register may be zero, which is an illegal value 245 flags_utime = flags_utime + 1; 246 tm->tm_mday = 1; 247 } 248 249 /* tm->tm_mon is zero-based */ 250 tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1; 251 252 if (tm->tm_mon < 0) { 253 flags_utime = flags_utime + 1; 254 tm->tm_mon = 0; 255 } 256 257 /* year is 1900 + tm->tm_year */ 258 tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100; 259 260 if (flags_utime > 0) { 262 } 263 264 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " 265 "mday=%d, mon=%d, year=%d, wday=%d\n", 266 __func__, 267 tm->tm_sec, tm->tm_min, tm->tm_hour, 268 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 269 270 return 0; 271 } 272 274 { 275 struct i2c_client *client = to_i2c_client(dev); 276 struct rs5c372 *rs5c = i2c_get_clientdata(client); 277 unsigned char buf[7]; 278 unsigned char ctrl2; 279 int addr; 280 281 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d " 282 "mday=%d, mon=%d, year=%d, wday=%d\n", 283 __func__, 284 tm->tm_sec, tm->tm_min, tm->tm_hour, 285 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 286 287 addr = RS5C_ADDR(RS5C372_REG_SECS); 288 buf[0] = bin2bcd(tm->tm_sec); 289 buf[1] = bin2bcd(tm->tm_min); 290 buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour); 291 buf[3] = bin2bcd(tm->tm_wday); 292 buf[4] = bin2bcd(tm->tm_mday); 293 buf[5] = bin2bcd(tm->tm_mon + 1); 294 buf[6] = bin2bcd(tm->tm_year - 100); 295 296 if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) { 297 dev_dbg(&client->dev, "%s: write error in line %i\n", 298 __func__, __LINE__); 299 return -EIO; 300 } 301 302 addr = RS5C_ADDR(RS5C_REG_CTRL2); 303 ctrl2 = i2c_smbus_read_byte_data(client, addr); 304 305 /* clear rtc warning bits */ 306 switch (rs5c->type) { 307 case rtc_r2025sd: 308 case rtc_r2221tl: 309 ctrl2 &= ~(R2x2x_CTRL2_VDET | R2x2x_CTRL2_PON); 310 if (rs5c->type == rtc_r2025sd) 311 ctrl2 |= R2x2x_CTRL2_XSTP; 312 else 313 ctrl2 &= ~R2x2x_CTRL2_XSTP; 314 break; 315 default: 316 ctrl2 &= ~RS5C_CTRL2_XSTP; 317 break; 318 } 319 320 if (i2c_smbus_write_byte_data(client, addr, ctrl2) < 0) { 321 dev_dbg(&client->dev, "%s: write error in line %i\n", 322 __func__, __LINE__); 323 return -EIO; 324 } 325 326 return 0; 327 } 328 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org