[bug report] scsi: ufs: ufs-exynos: Add UFS host support for Exynos SoCs

Dan Carpenter
2021-07-27T09:46:40Z

Hello Alim Akhtar,

The patch 55f4b1f73631: "scsi: ufs: ufs-exynos: Add UFS host support
for Exynos SoCs" from May 28, 2020, leads to the following static
checker warning:

drivers/scsi/ufs/ufs-exynos.c:286 exynos_ufs_get_clk_info()
warn: wrong type for 'ufs->mclk_rate' (should be 'ulong')

drivers/scsi/ufs/ufs-exynos.c:287 exynos_ufs_get_clk_info()
warn: wrong type for 'pclk_rate' (should be 'ulong')

drivers/scsi/ufs/ufs-exynos.c
258 static int exynos_ufs_get_clk_info(struct exynos_ufs *ufs)
259 {
260 struct ufs_hba *hba = ufs->hba;
261 struct list_head *head = &hba->clk_list_head;
262 struct ufs_clk_info *clki;
263 u32 pclk_rate;
^^^^^^^^^^^^^

264 u32 f_min, f_max;
265 u8 div = 0;
266 int ret = 0;
267
268 if (list_empty(head))
269 goto out;
270
271 list_for_each_entry(clki, head, list) {
272 if (!IS_ERR(clki->clk)) {
273 if (!strcmp(clki->name, "core_clk"))
274 ufs->clk_hci_core = clki->clk;
275 else if (!strcmp(clki->name, "sclk_unipro_main"))
276 ufs->clk_unipro_main = clki->clk;
277 }
278 }
279
280 if (!ufs->clk_hci_core || !ufs->clk_unipro_main) {
281 dev_err(hba->dev, "failed to get clk info\n");
282 ret = -EINVAL;
283 goto out;
284 }
285
--> 286 ufs->mclk_rate = clk_get_rate(ufs->clk_unipro_main);
--> 287 pclk_rate = clk_get_rate(ufs->clk_hci_core);

This a new Smatch warning which is not yet pushed. The clk_get_rate()
function returns unsigned long so I guess ufs->mclk_rate and pclk_rate
should be changed from u32. Not sure the runtime impact.

288 f_min = ufs->pclk_avail_min;
289 f_max = ufs->pclk_avail_max;
290
291 if (ufs->opts & EXYNOS_UFS_OPT_HAS_APB_CLK_CTRL) {
292 do {
293 pclk_rate /= (div + 1);
294
295 if (pclk_rate <= f_max)
296 break;
297 div++;
298 } while (pclk_rate >= f_min);
299 }
300
301 if (unlikely(pclk_rate < f_min || pclk_rate > f_max)) {
302 dev_err(hba->dev, "not available pclk range %d\n", pclk_rate);
303 ret = -EINVAL;
304 goto out;
305 }
306
307 ufs->pclk_rate = pclk_rate;
308 ufs->pclk_div = div;
309
310 out:
311 return ret;
312 }

regards,
dan carpenter